subject:(Magnets)

Michigan State University

1. Parker, Rolin James. Magnetic stability studies of SmCo₅ permanent magnets.

Degree: MS, Dept. of Metallurgy, Mechanics, and Materials Sciences, 1973, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:7157

Subjects/Keywords: Magnets

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APA (6^th Edition):

Parker, R. J. (1973). Magnetic stability studies of SmCo₅ permanent magnets. (Masters Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:7157

Chicago Manual of Style (16^th Edition):

Parker, Rolin James. “Magnetic stability studies of SmCo₅ permanent magnets.” 1973. Masters Thesis, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:7157.

MLA Handbook (7^th Edition):

Parker, Rolin James. “Magnetic stability studies of SmCo₅ permanent magnets.” 1973. Web. 01 Mar 2021.

Vancouver:

Parker RJ. Magnetic stability studies of SmCo₅ permanent magnets. [Internet] [Masters thesis]. Michigan State University; 1973. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:7157.

Council of Science Editors:

Parker RJ. Magnetic stability studies of SmCo₅ permanent magnets. [Masters Thesis]. Michigan State University; 1973. Available from: http://etd.lib.msu.edu/islandora/object/etd:7157

McGill University

2. Dyck, Derek. Intensity fluctuation spectroscopy with coherent X-rays.

Degree: PhD, Department of Electrical Engineering, 1995, McGill University

URL: https://escholarship.mcgill.ca/downloads/cc08hh903.pdf ; https://escholarship.mcgill.ca/concern/theses/6m311r72v

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This thesis presents a system for automating the design of magnetic devices such as induction motors, transformers, and alternators. The search space of possible designs… (more)

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This thesis presents a system for automating the design of magnetic devices such as induction motors, transformers, and alternators. The search space of possible designs is parameterized using a universal representation of devices which basically specifies the distribution of material at every point in space. The design specifications are input in the form of a mathematical function, design is performed by optimizing this objective function. Output consists of a set of grey-scale pixel-like images of the distribution of the different materials in the device. From the perspective of artificial intelligence, the system is based on the first principles of magnetic devices, i.e. Maxwell's equations. Since no other know ledge is embedded in the system, it has the potential of discovering original devices to solve long-standing design problems, and also to solve design problems for which no human expertise exists.

Cette thèse présente un système automatique de conception de dispositifs électromagnétiques tels que les moteurs asynchrones, les transformateurs et les alternateurs. L'espace de faisabilité est paramétrise par une représentation universelle des dispositifs dont les matériaux constitutifs sont indiqués à chaque point dans l'espace. Les données sont fournies sous forme d'une fonction mathématique qui représente les spécifications du dispositif, et la conception automatique est accomplie par l'optimisation de cette fonction objective. La sortie du système est un ensemble d'images en différents tons de gris qui représentent la disposition des matériaux constitutifs du dispositif. Du point de vue de l'intelligence artificielle, le système est fondé sur les premiers principes de la théorie des dispositifs magnétiques, c'est à dire les équations de Maxwell. A part de ces premiers principes, aucune autre connaissance n'est incluse dans le système. Ce dernier a donc la capacité de trouver des conceptions originales à la solution des problèmes classiques, il peut également résoudre des problèmes de conception pour lesquels il n'y a aucune expertise humaine.

Advisors/Committee Members: Lowther, David A. (Supervisor).

Subjects/Keywords: Magnets

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APA (6^th Edition):

Dyck, D. (1995). Intensity fluctuation spectroscopy with coherent X-rays. (Doctoral Dissertation). McGill University. Retrieved from https://escholarship.mcgill.ca/downloads/cc08hh903.pdf ; https://escholarship.mcgill.ca/concern/theses/6m311r72v

Chicago Manual of Style (16^th Edition):

Dyck, Derek. “Intensity fluctuation spectroscopy with coherent X-rays.” 1995. Doctoral Dissertation, McGill University. Accessed March 01, 2021. https://escholarship.mcgill.ca/downloads/cc08hh903.pdf ; https://escholarship.mcgill.ca/concern/theses/6m311r72v.

MLA Handbook (7^th Edition):

Dyck, Derek. “Intensity fluctuation spectroscopy with coherent X-rays.” 1995. Web. 01 Mar 2021.

Vancouver:

Dyck D. Intensity fluctuation spectroscopy with coherent X-rays. [Internet] [Doctoral dissertation]. McGill University; 1995. [cited 2021 Mar 01]. Available from: https://escholarship.mcgill.ca/downloads/cc08hh903.pdf ; https://escholarship.mcgill.ca/concern/theses/6m311r72v.

Council of Science Editors:

Dyck D. Intensity fluctuation spectroscopy with coherent X-rays. [Doctoral Dissertation]. McGill University; 1995. Available from: https://escholarship.mcgill.ca/downloads/cc08hh903.pdf ; https://escholarship.mcgill.ca/concern/theses/6m311r72v

Boston College

3. Hou, Wentao. Thermally Driven Topology in Chiral Magnets.

Degree: PhD, Physics, 2019, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:108694

► Magnetism is an old field in condensed matter physics, but it is still vibrant and full of excitement. Regardless of deep fundamental physics therein, it… (more)

▼ Magnetism is an old field in condensed matter physics, but it is still vibrant and full of excitement. Regardless of deep fundamental physics therein, it also has broad application in engineering technology, modern hard disk drive as an example. Magnetic skyrmion, a vortex-like structure in two-dimensional magnetic systems, has been discovered in various magnetic materials, among which chiral magnets are a family of candidates. The skyrmions are characterized by nonzero topological charges. The vortex-like structure of skyrmions makes skyrmion materials good candidates of new generation of data storage device. So understanding the transport properties of the skyrmion materials is important for the possible application in the future. The Hall effect is a key aspect of electron transports. The topological Hall effect, which is one component in the total Hall effect, only depends on the magnetic structures, and the topological Hall conductivity is proportional to the topological charge. It thus serves as the transport signature of magnetic skyrmions. The major mission of this thesis is to investigate the topological charge distribution in realistic models and uncover the relationship between the existence of skyrmions and other chiral excitations. The organization of the thesis is the following. The first chapter is the introduction. A historical survey about magnetic skyrmions and chiral magnets is presented firstly. The magnetic skyrmion is identified by the topological charge. Further, the relationship between the topological hall effect and topological charge is described by the emergent electrodynamics. The importance of the topological charge in chiral magnets is explained in this part. Following the importance of the topological charge, the investigation of topological charge in two-dimensional chiral magnets is presented in the second chapter. The Monte Carlo simulation is employed to calculate the topological charge on a square lattice. The results show that the nonzero topological charge is not necessarily correlated to the existence of skyrmions in chiral magnets. To understand the numerical results, simple analysis based on the physical picture of a triangle on the square lattice is performed. Then we calculate the topological charge in continuum model of chiral magnets. At the high temperature limit, the numerical results, picture analysis and the analytic result are consistent. Then, in this chapter, there is a description of the recent experimental work on thin film SrRuO3 which confirmed our theoretical prediction. A discussion on spin chirality, topological charge and Hall conductivity is presented in the end. However, no experiment on chiral magnets has been on a perfect monolayer system. So we extend the investigation of topological charge into three-dimensional situation. This work is introduced in the third chapter. The Monte Carlo simulation and the analytical calculation are presented firstly. A special issue in three-dimensional chiral magnets is the thickness dependence. The Monte Carlo… Advisors/Committee Members: Ziqiang . Wang (Thesis advisor), Jiadong . Zang (Thesis advisor).

Subjects/Keywords: Chiral magnets

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APA (6^th Edition):

Hou, W. (2019). Thermally Driven Topology in Chiral Magnets. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:108694

Chicago Manual of Style (16^th Edition):

Hou, Wentao. “Thermally Driven Topology in Chiral Magnets.” 2019. Doctoral Dissertation, Boston College. Accessed March 01, 2021. http://dlib.bc.edu/islandora/object/bc-ir:108694.

MLA Handbook (7^th Edition):

Hou, Wentao. “Thermally Driven Topology in Chiral Magnets.” 2019. Web. 01 Mar 2021.

Vancouver:

Hou W. Thermally Driven Topology in Chiral Magnets. [Internet] [Doctoral dissertation]. Boston College; 2019. [cited 2021 Mar 01]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108694.

Council of Science Editors:

Hou W. Thermally Driven Topology in Chiral Magnets. [Doctoral Dissertation]. Boston College; 2019. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108694

Texas A&M University

4. Southerland, Heather Irene. Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates.

Degree: PhD, Chemistry, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151035

► The field of molecular magnetism has expanded rapidly since the discovery of single molecule magnets (SMMs) in the 1990’s and has witnessed extraordinary advances in… (more)

▼ The field of molecular magnetism has expanded rapidly since the discovery of single molecule magnets (SMMs) in the 1990’s and has witnessed extraordinary advances in the last several decades. One of the current trends in molecular magnetic research is to incorporate metal ions that have pronounced single-ion anisotropy in an effort to improve magnetic exchange interactions. The 4d and 5d transition metal ions have large spin-orbit coupling parameters which contribute to the orbital angular momentum effects that lead to anisotropic behavior. The work herein describes efforts to synthesize and characterize new cyanide-bridged molecular materials incorporating 4d and 5d transition metal ions, specifically the [Os(CN)_(6)]^(3-), [Mo(CN)_(6)]^(3-) and [W(CN)_(8)]^(3-) ions. The 5d hexacyanometallate [Os(CN)_(6)]^(3-) was incorporated into a trinuclear cyanide bridged molecule and the [Fe(CN)_(6)]^(3-) analog was prepared as a reference compound for assessing the effect of the 5d versus 3d metal ion on the magnetic properties. Both molecules exhibit SMM bistability with a pronounced increase (~90 %) in the blocking temperature (TB) of the OsIII analogue. In addition to typical SMM behavior, both compounds exhibit exchange-biased SMM behavior, a shift in the quantum tunneling of the magnetization (QTM) from zero field. This exchange-bias can be turned “on” or “off” depending on the presence of interstitial methanol molecules. New trigonal bipyramidal (TBP) molecules incorporating the rarely studies hexacyanomolybdate(III) ion are presented in chapter III of this dissertation. The molecules of general formula [M(tmphen)_(2)]_(3)[Mo(CN)_(6)]_(2) (M = V^(II), Mn^(II) and Fe^(II); tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline), represent additions to a large homologous family of TBP molecules reported by the Dunbar group over the years. The [Mo(CN)_(6)]^(3-) ion was prepared in situ by loss of one cyanide ligand from [Mo(CN)_(7)]^(4-). Of particular interest among the compounds reported is the V_(3)Mo_(2) analog which exhibits extraordinarily strong antiferromagnetic coupling (estimated J = -134 cm^(-1). The observed exchange coupling parameter is more than twice the current record for the antiferromagnetic coupling parameter for a cyanide-bridged magnetic molecule. Another set of results were obtained using the octacyanometallate anion [WV(CN)_(8)]^(3-) as a building block for the synthesis and magnetic studies of a family of new cyanide-bridged magnetic materials. The compounds exhibit several different structural motifs including three 0-D molecular compounds (two pentanuclear molecules and a linear trinuclear molecule) and a 1-D chain, findings that illustrate the structural versatility of the octacyanotungstate(V) ions. The TBP molecule, [Mn(tmphen)_(2)]_(3)[W(CN)_(8)]_(2), exhibits evidence for an out-of-phase signal when subjected to ac measurements in zero applied field. The 1-D chain also reveals evidence for the beginning of an out-of-phase signal under zero applied field which hints at single… Advisors/Committee Members: Dunbar, Kim R. (advisor), Hughbanks, Timothy R. (committee member), Zhou, Hong-Cai (committee member), Roshchin, Igor V. (committee member).

Subjects/Keywords: Single Molecule Magnets; Exchange Bias; Molecular Magnets

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APA (6^th Edition):

Southerland, H. I. (2013). Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151035

Chicago Manual of Style (16^th Edition):

Southerland, Heather Irene. “Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates.” 2013. Doctoral Dissertation, Texas A&M University. Accessed March 01, 2021. http://hdl.handle.net/1969.1/151035.

MLA Handbook (7^th Edition):

Southerland, Heather Irene. “Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates.” 2013. Web. 01 Mar 2021.

Vancouver:

Southerland HI. Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1969.1/151035.

Council of Science Editors:

Southerland HI. Investigation of Molecular Magnetic Compounds Incorporating 4d and 5d Transition Metal Cyanometallates. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151035

Princeton University

5. Zhang, Songtian Sonia. Topology in Quantum Magnets and Superconductors .

Degree: PhD, 2020, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01jm214s07s

► A unifying theme in understanding the macroscopic properties of quantum materials is the concept of emergence, where novel effects and unusual phases arise from the… (more)

Subjects/Keywords: Kagome magnets; Quantum magnets; Superconductors; Topology

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APA (6^th Edition):

Zhang, S. S. (2020). Topology in Quantum Magnets and Superconductors . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01jm214s07s

Chicago Manual of Style (16^th Edition):

Zhang, Songtian Sonia. “Topology in Quantum Magnets and Superconductors .” 2020. Doctoral Dissertation, Princeton University. Accessed March 01, 2021. http://arks.princeton.edu/ark:/88435/dsp01jm214s07s.

MLA Handbook (7^th Edition):

Zhang, Songtian Sonia. “Topology in Quantum Magnets and Superconductors .” 2020. Web. 01 Mar 2021.

Vancouver:

Zhang SS. Topology in Quantum Magnets and Superconductors . [Internet] [Doctoral dissertation]. Princeton University; 2020. [cited 2021 Mar 01]. Available from: http://arks.princeton.edu/ark:/88435/dsp01jm214s07s.

Council of Science Editors:

Zhang SS. Topology in Quantum Magnets and Superconductors . [Doctoral Dissertation]. Princeton University; 2020. Available from: http://arks.princeton.edu/ark:/88435/dsp01jm214s07s

Rutgers University

6. Gao, Bin, 1986-. Hybrid improper ferroelectrics and polar magnets.

Degree: PhD, Physics and Astronomy, 2017, Rutgers University

URL: https://rucore.libraries.rutgers.edu/rutgers-lib/53622/

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This dissertation seeks to study some polar magnets, especially hybrid improper ferroelectricity (HIF), one promising candidate to realize room{temperature multiferroics. In order to realize the… (more)

Subjects/Keywords: Ferromagnetic materials; Magnets

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APA (6^th Edition):

Gao, Bin, 1. (2017). Hybrid improper ferroelectrics and polar magnets. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/53622/

Chicago Manual of Style (16^th Edition):

Gao, Bin, 1986-. “Hybrid improper ferroelectrics and polar magnets.” 2017. Doctoral Dissertation, Rutgers University. Accessed March 01, 2021. https://rucore.libraries.rutgers.edu/rutgers-lib/53622/.

MLA Handbook (7^th Edition):

Gao, Bin, 1986-. “Hybrid improper ferroelectrics and polar magnets.” 2017. Web. 01 Mar 2021.

Vancouver:

Gao, Bin 1. Hybrid improper ferroelectrics and polar magnets. [Internet] [Doctoral dissertation]. Rutgers University; 2017. [cited 2021 Mar 01]. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/53622/.

Council of Science Editors:

Gao, Bin 1. Hybrid improper ferroelectrics and polar magnets. [Doctoral Dissertation]. Rutgers University; 2017. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/53622/

Colorado State University

7. Newell, Brian S. Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies.

Degree: PhD, Chemistry, 2011, Colorado State University

URL: http://hdl.handle.net/10217/70463

► This dissertation describes the synthesis of multinuclear compounds that possess magnetically-coupled actinide, namely uranium-238, clusters. These assemblies are supported by both acetylide-type ligands as well… (more)

▼ This dissertation describes the synthesis of multinuclear compounds that possess magnetically-coupled actinide, namely uranium-238, clusters. These assemblies are supported by both acetylide-type ligands as well as triamidoamine or softer phosphine ligands. Synthetic inorganic chemists have been able to synthesize molecules and clusters with increased spin, S, or axial anisotropy, D, in an effort to augment the spin-reversal barriers and create better single-molecule magnets (SMMs). However, efforts to simultaneously increase these parameters are complicated. One potential route utilizes heavy atoms as a result of their larger single-ion anisotropy and believed ability to modulate the magnetism of other systems. My research is placed in this context in Chapter 1, where recent efforts to incorporate heavy atoms into expanded clusters are discussed. In Chapter 2, the preparation and magnetic property investigations of a structurally related family of mono-, di- and trinuclear U(IV) aryl acetylide complexes are presented. The reaction between [(NN′3)UCl] and lithiated aryl acetylides leads to the formation of hexacoordinate compounds. In contrast, combining the uranacycle [(bit-NN′3)U] (bit-NN′3 = [N(CH2CH2NSitBuMe2)2(CH2CH2SitBuMeCH2]) with stoichiometric amounts of mono-, bis-, and tris(ethynyl) benzenes affords pentacoordinate arylacetylide complexes, where NN′3 = [N(CH2CH2NSitBuMe2)3]. The measured magnetic susceptibilities for these compounds trend toward non-magnetic ground states at low temperatures. Nevertheless, the di- and trinuclear pentacoordinate compounds appear to display weak magnetic communication between the uranium centers. This communication is modeled by fitting of the DC magnetic susceptibility data, using the spin Hamiltonian. Geometry-optimized Stuttgart/6-31g* B3LYP hybrid DFT calculations were carried out (spin-orbit coupling omitted) on model complexes and the electrochemistry of the monomeric phenylacetylide complex exhibits a reversible redox couple at -1.02 V versus [Cp2Fe]+/0, assignable to an oxidation of U(IV) to U(V). Efforts to study the magnetic correlations as a result of cubic ligands fields are presented in Chapter 3, whereby a neutral bidentate phosphine ligand was utilized. In the course of structurally characterizing previously reported complexes based on the 1,2-bis(dimethylphosphino)ethane)) (dmpe) ligand ([(dmpe)2UCl4] (3.1) and [(dmpe)2UMe4] (3.2)), we found that adjusting the U:dmpe ratio leads to an unprecedented species. Whereas the use of two or three equivalents of dmpe relative to UCl4 produces 3.1 as a blue-green solid, use of a 1:1 dmpe:UCl4 stoichiometry yields [(dmpe)4U4Cl16]•2CH2Cl2•(3.3•2CH2Cl2) as a green solid. In turn, 3.3 is used to prepare a mixed-chelating ligand complex featuring the bidentate ligand 4,4′-dimethyl-2,2′-bipyridine (dmbpy), [(dmpe)(dmbpy)UCl4] (3.4). The measured magnetic susceptibilities for 3.1-3.4 trend toward non-magnetic ground states at low temperatures. In Chapter 4, we hypothesized that preparing… Advisors/Committee Members: Shores, Matthew P. (advisor), Anderson, Oren P. (advisor), Chen, Eugene Y. (committee member), Levinger, Nancy E. (committee member), Wu, Mingzhong (committee member).

Subjects/Keywords: actinides; single molecule magnets; magnetism

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APA (6^th Edition):

Newell, B. S. (2011). Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/70463

Chicago Manual of Style (16^th Edition):

Newell, Brian S. “Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies.” 2011. Doctoral Dissertation, Colorado State University. Accessed March 01, 2021. http://hdl.handle.net/10217/70463.

MLA Handbook (7^th Edition):

Newell, Brian S. “Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies.” 2011. Web. 01 Mar 2021.

Vancouver:

Newell BS. Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies. [Internet] [Doctoral dissertation]. Colorado State University; 2011. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10217/70463.

Council of Science Editors:

Newell BS. Synthesis and characterization of uranium(IV) compounds: from mononuclear complexes to multinuclear assemblies. [Doctoral Dissertation]. Colorado State University; 2011. Available from: http://hdl.handle.net/10217/70463

Delft University of Technology

8. Westerman, S.C.H. (author). Design of a statically balanced mechanism using magnets and springs.

Degree: 2015, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:ec1986f1-d28e-47cc-a22b-caeb6fb3003b

►

The current work presents a statically balanced system with novel design, which incorporates compression springs as a positive stiffness and magnets as a negative stiffness.… (more)

Subjects/Keywords: statically; balanced; mechanism; magnets; springs

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APA (6^th Edition):

Westerman, S. C. H. (. (2015). Design of a statically balanced mechanism using magnets and springs. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:ec1986f1-d28e-47cc-a22b-caeb6fb3003b

Chicago Manual of Style (16^th Edition):

Westerman, S C H (author). “Design of a statically balanced mechanism using magnets and springs.” 2015. Masters Thesis, Delft University of Technology. Accessed March 01, 2021. http://resolver.tudelft.nl/uuid:ec1986f1-d28e-47cc-a22b-caeb6fb3003b.

MLA Handbook (7^th Edition):

Westerman, S C H (author). “Design of a statically balanced mechanism using magnets and springs.” 2015. Web. 01 Mar 2021.

Vancouver:

Westerman SCH(. Design of a statically balanced mechanism using magnets and springs. [Internet] [Masters thesis]. Delft University of Technology; 2015. [cited 2021 Mar 01]. Available from: http://resolver.tudelft.nl/uuid:ec1986f1-d28e-47cc-a22b-caeb6fb3003b.

Council of Science Editors:

Westerman SCH(. Design of a statically balanced mechanism using magnets and springs. [Masters Thesis]. Delft University of Technology; 2015. Available from: http://resolver.tudelft.nl/uuid:ec1986f1-d28e-47cc-a22b-caeb6fb3003b

Michigan State University

9. Oppermann, Dean Alan. P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis.

Degree: PhD, Department of Materials Science and Mechanics, 2000, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:30293

Subjects/Keywords: Chondrogenesis; Magnets

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APA (6^th Edition):

Oppermann, D. A. (2000). P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis. (Doctoral Dissertation). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:30293

Chicago Manual of Style (16^th Edition):

Oppermann, Dean Alan. “P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis.” 2000. Doctoral Dissertation, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:30293.

MLA Handbook (7^th Edition):

Oppermann, Dean Alan. “P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis.” 2000. Web. 01 Mar 2021.

Vancouver:

Oppermann DA. P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis. [Internet] [Doctoral dissertation]. Michigan State University; 2000. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:30293.

Council of Science Editors:

Oppermann DA. P(dl)A/PGA/FE and P(dl)A/PGA/SmCo₅ composites for use as a delivery mechanism for magnetically directed chondrogenesis. [Doctoral Dissertation]. Michigan State University; 2000. Available from: http://etd.lib.msu.edu/islandora/object/etd:30293

10. Stavretis, Shelby Elizabeth. Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering.

Degree: 2018, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/4920

► The primary focus of this dissertation is using inelastic neutron scattering (INS) to probe magnetic excitations in paramagnetic complexes including single-molecule magnets (SMMs). Other related… (more)

▼ The primary focus of this dissertation is using inelastic neutron scattering (INS) to probe magnetic excitations in paramagnetic complexes including single-molecule magnets (SMMs). Other related studies include the following: (1) Simulating vibrational frequencies to understand spin-phonon coupling (SPC) in a single-molecule magnet; (2) Using quasi-elastic neutron scattering (QENS) to study molecular dynamics of a paramagnet. Zero-field splitting (ZFS) parameters (axial: D and rhombic: E) of metalloporphryins Fe(TPP)X [X = F, Br, I; H2TPP = tetraphenylporphyrin] have been directly determined by INS. These studies provide a complete determination of ZFS parameters for a metalloporphryin halide series demonstrating that D increases from F to I complexes. Ab initio methods were led to the understanding of the origin of the halide trend. INS has also been used to probe several Co(II) and an Er(III) SMMs. The magnetic excitations were determined by a variety of methods demonstrating that INS is a unique technique to determine the magnitude of these excitations. Most prominently, INS conducted under variable magnetic fields, reveals magnetic excitations in single crystals and powder samples in the energy region above 40 cm-1. In addition, this work shows a unique strength of INS to show the origin of spin-phonon entangled peaks at 0 T. Vibrational frequencies and simulation of atomic displacements in Co(II) SMMs have been calculated via ab intio methods to study SPC. Raman spectroscopy of Co(acac)2(H2O)2 (acac = acetylacetonate), Co(acac)2(D2O)2 and Co(acac-d7)2(D2O)2 gives experimental SPC constants of different magnitudes. By probing the displacements in atoms in the SMMs, a correlation between the largest bond angle change in the first coordination sphere and largest SPC constant has been discovered. This work leads to understanding of how the electron spins in the Co(II) complexes interact with phonons in the energy region near the magnetic excitation. QENS has been used to study methyl rotation in Co(acac)2(D2O)2, which behaves as a paramagnet in the temperature range probed (80–100 K). The use of external magnetic fields leads to the observation of field-dependent methyl rotation. This field-dependent behavior sheds light on intermolecular interactions in the solid state.

Subjects/Keywords: Neutron Scattering; Single Molecule Magnets

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APA (6^th Edition):

Stavretis, S. E. (2018). Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/4920

Chicago Manual of Style (16^th Edition):

Stavretis, Shelby Elizabeth. “Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering.” 2018. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed March 01, 2021. https://trace.tennessee.edu/utk_graddiss/4920.

MLA Handbook (7^th Edition):

Stavretis, Shelby Elizabeth. “Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering.” 2018. Web. 01 Mar 2021.

Vancouver:

Stavretis SE. Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2018. [cited 2021 Mar 01]. Available from: https://trace.tennessee.edu/utk_graddiss/4920.

Council of Science Editors:

Stavretis SE. Probing Magnetic and Vibrational Properties of Molecular Compounds by Neutron Scattering. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2018. Available from: https://trace.tennessee.edu/utk_graddiss/4920

University of Edinburgh

11. Rigonat, Nicola. Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities.

Degree: PhD, 2017, University of Edinburgh

URL: http://hdl.handle.net/1842/28743

► The UK Committee on Radioactive Waste Management (CoRWM) recommended, in 2006, that geological disposal coupled with safe and secure interim storage should have been the… (more)

▼ The UK Committee on Radioactive Waste Management (CoRWM) recommended, in 2006, that geological disposal coupled with safe and secure interim storage should have been the way forward for the long-term management of the UK’s higher activity wastes. The design of the underground repository contemplates the presence of bentonite plugs to seal access galleries and deposition boreholes and hence the interaction between the clay-based backfill material and the underground water. Remote monitoring of the fluid saturation of the barrier, the waste canisters and of the surrounding subsurface Geological Disposal Facility environment assumes a relevant importance to guarantee the safety of the repository and to increase the confidence and the reliance of the communities living in areas potentially affected by the repository over time. This remote monitoring of the Engineered Barrier System represents a technical challenge due to the unsuitability of some of the traditional geotechnical techniques or to the intrinsic unreliability of many geophysical prospecting techniques in providing information about the evolution of the Thermo-Hydro-Mechanical-Chemical coupling of the system over long timescales up to and including post-closure evolution. In this project, I offer an initial approach to an innovative way of using mineral magnetism, and, in particular, I analyse the possible exploitation of corrosion-induced variations of the magnetic properties of several magnetic materials to monitor water saturation in the Engineered Barrier System and its evolution through time. Initially the reactivity of several natural and synthetic materials is tested under different “extreme” conditions to analyse the feasibility of the research concept and identify the materials more adapt to carry out the job. The effects that the corrosion of the magnetic materials has on the clay matrix is also analysed in detail throughout all the thesis work. The initial tests lead to the identification of specific transitions in the hysteretic behaviour of three of the initial candidates (Nd-Fe-B, AlNiCo and SmCo alloys). These three materials are subsequently tested under conditions closer to a real “evolved” Barrier System, where the groundwater interacts, with cementiferous grout producing hyperalkaline leachates. The final tests consider the temporal evolution (after 4, 8 and 12 months) of the magnetic properties of these materials in a dysoxic environment under imposed fluid-flow. The results show a clear change in the hysteretic properties of the three materials analysed and the feasibility of the monitoring of the Barrier fluid saturation in the short-term. Furthermore, the corrosion of the magnets, under the conditions applied, did not cause formation of non-swelling clays.

Subjects/Keywords: geological disposal; barriers; magnets; bentonite

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rigonat, N. (2017). Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/28743

Chicago Manual of Style (16^th Edition):

Rigonat, Nicola. “Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities.” 2017. Doctoral Dissertation, University of Edinburgh. Accessed March 01, 2021. http://hdl.handle.net/1842/28743.

MLA Handbook (7^th Edition):

Rigonat, Nicola. “Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities.” 2017. Web. 01 Mar 2021.

Vancouver:

Rigonat N. Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities. [Internet] [Doctoral dissertation]. University of Edinburgh; 2017. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1842/28743.

Council of Science Editors:

Rigonat N. Development of a novel magnetic monitoring system for engineered barriers of geological disposal facilities. [Doctoral Dissertation]. University of Edinburgh; 2017. Available from: http://hdl.handle.net/1842/28743

Virginia Tech

12. Mccaskey, Alexander Joseph. Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach.

Degree: MS, Physics, 2014, Virginia Tech

URL: http://hdl.handle.net/10919/48026

► Recent experiments have shown that junctions consisting of individual single-molecule magnets (SMMs) bridged between two electrodes can be fabricated in three-terminal devices, and that the… (more)

Subjects/Keywords: Single-Molecule Magnets; Electron Transport

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APA (6^th Edition):

Mccaskey, A. J. (2014). Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/48026

Chicago Manual of Style (16^th Edition):

Mccaskey, Alexander Joseph. “Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach.” 2014. Masters Thesis, Virginia Tech. Accessed March 01, 2021. http://hdl.handle.net/10919/48026.

MLA Handbook (7^th Edition):

Mccaskey, Alexander Joseph. “Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach.” 2014. Web. 01 Mar 2021.

Vancouver:

Mccaskey AJ. Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach. [Internet] [Masters thesis]. Virginia Tech; 2014. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10919/48026.

Council of Science Editors:

Mccaskey AJ. Effects of Electron-Vibron Coupling in Single-Molecule Magnet Transport Junctions Using a Hybrid Density Functional Theory and Model Hamiltonian Approach. [Masters Thesis]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/48026

University of British Columbia

13. Oraas, Sherman Roy. Techniques applied to the design of the TRIUMF magnet poles.

Degree: Master of Applied Science - MASc, Physics, 1970, University of British Columbia

URL: http://hdl.handle.net/2429/34531

► This thesis presents some of the techniques used in designing the sector-focused magnet for the TRIUMF cyclotron. An empirical method is given for calculating the… (more)

Subjects/Keywords: Magnets.; Cyclotrons.

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APA (6^th Edition):

Oraas, S. R. (1970). Techniques applied to the design of the TRIUMF magnet poles. (Masters Thesis). University of British Columbia. Retrieved from http://hdl.handle.net/2429/34531

Chicago Manual of Style (16^th Edition):

Oraas, Sherman Roy. “Techniques applied to the design of the TRIUMF magnet poles.” 1970. Masters Thesis, University of British Columbia. Accessed March 01, 2021. http://hdl.handle.net/2429/34531.

MLA Handbook (7^th Edition):

Oraas, Sherman Roy. “Techniques applied to the design of the TRIUMF magnet poles.” 1970. Web. 01 Mar 2021.

Vancouver:

Oraas SR. Techniques applied to the design of the TRIUMF magnet poles. [Internet] [Masters thesis]. University of British Columbia; 1970. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/2429/34531.

Council of Science Editors:

Oraas SR. Techniques applied to the design of the TRIUMF magnet poles. [Masters Thesis]. University of British Columbia; 1970. Available from: http://hdl.handle.net/2429/34531

Georgia Tech

14. Bai, Xiaojian. Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials.

Degree: PhD, Physics, 2019, Georgia Tech

URL: http://hdl.handle.net/1853/64040

► The basic theme of my Ph.D. research is understanding exotic magnetic phases of matter and investigate their collective low-energy excitations using neutron-scattering and quantitative modeling.… (more)

▼ The basic theme of my Ph.D. research is understanding exotic magnetic phases of matter and investigate their collective low-energy excitations using neutron-scattering and quantitative modeling. In this thesis, I start with an attempt to answer a list of questions that I had in the beginning of my Ph.D. study, such as why we can use a simple effective model to describe this complex world, how to synthesize and characterize samples, how to analyze the data and find a good theoretical model and many more. There is no unique answer to these questions. I speak from experience and hope to provide a road map to whoever read my thesis and is interested in starting condensed matter research using neutron-scattering. Next, I present two material projects that I assume a major role. In both projects, high resolution single-crystal inelastic neutron-scattering data enables me and my collaborators to make significantly advances in understanding complex dynamical responses of magnetic materials. In Chapter 2, I present our study on a canonical frustrated magnet MgCr2O4 in the deep cooperative paramagnetic regime. In experiment, we observe a highly structured elastic scattering pattern with continuous excitation spectrum. Using analytic and computational methods, we reveal the highly correlated spin state is proximate to a "spiral spin-liquid" phase and the collective excitations are predominantly fast harmonic precessions of spin on a slow-varying disordered background. In Chapter 3, I present our study on an enigmatic compound with prior investigations dated back to 1970s – FeI2. In experiment, we observe a bright and dispersive band with "quadrupolar" character, apparently at odds with the dipole selection rule. Using advance numerical techniques, we are able to fully account for this band via a novel hybridization mechanism involving off-diagonal symmetric exchange interactions. In Chapter 4, I introduce detailed implementations of spin dynamics simulations and application to a realistic diamond-lattice system. This technique provides a simple framework to study finite temperature and non-linear effects of complex magnetic materials and has increasingly been used to study disordered and strongly-correlated spin systems. I close this thesis in Chapter 5 with an outlook of future directions. Advisors/Committee Members: Mourigal, Martin (advisor), Conrad, Edward H. (committee member), Rocklin, David Z. (committee member), Wilkinson, Angus P. (committee member), Evenbly, Glen (committee member).

Subjects/Keywords: Neutron Scattering; Frustrated Magnets

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APA (6^th Edition):

Bai, X. (2019). Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/64040

Chicago Manual of Style (16^th Edition):

Bai, Xiaojian. “Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials.” 2019. Doctoral Dissertation, Georgia Tech. Accessed March 01, 2021. http://hdl.handle.net/1853/64040.

MLA Handbook (7^th Edition):

Bai, Xiaojian. “Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials.” 2019. Web. 01 Mar 2021.

Vancouver:

Bai X. Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials. [Internet] [Doctoral dissertation]. Georgia Tech; 2019. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1853/64040.

Council of Science Editors:

Bai X. Neutron Scattering and Quantitative Modeling of Magnetic Excitations in Frustrated Materials. [Doctoral Dissertation]. Georgia Tech; 2019. Available from: http://hdl.handle.net/1853/64040

Stellenbosch University

15. Treurnicht, Anton. Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling.

Degree: MEng, Electrical and Electronic Engineering, 2017, Stellenbosch University

URL: http://hdl.handle.net/10019.1/101217

►

ENGLISH ABSTRACT: This project investigates the sensorless control of a new generation ironless non-salient pole permanent-magnet synchronous machine (IDRFPMSM) for wind-turbine genera- tor and electric-vehicle… (more)

▼

ENGLISH ABSTRACT: This project investigates the sensorless control of a new generation ironless non-salient pole permanent-magnet synchronous machine (IDRFPMSM) for wind-turbine genera- tor and electric-vehicle applications. Due to the nature of the ironless non-salient pole permanent-magnet synchronous machine, BEMF sensorless rotor position estimation techniques is mandatory. BEMF position-estimation techniques cannot be used at ro- tor standstill and low rotational speeds. In applications where e ciency is critical at low speed, a magnetic stray- eld position sensor was implemented to provide the rotor posi- tion below the minimum estimator speed, by measuring the magnetic stray- elds behind the Halbach permanent-magnet array. To provide the sensorless position estimator and the control system with accurate machine parameters, an open-loop parameter estimation technique is introduced for estimating all ve machine parameters at system power-on. This is augmented during closed-loop operation by updating the parameters with an on- line parameter estimator. A demonstrator was built to show that the combination of all of the closed-loop elements can be integrated with the IDRFPMSM machine. The results also show that the IDRFPMSM can be used in both sensorless generator and sensorless motor applications.

AFRIKAANSE OPSOMMING: Hierdie projek ondersoek die sensorlose beheer van 'n nuwe geslag ysterlose permanentemagneet- sinchroonmasjien met 'n ongesplete pool vir gebruik by windopwekkers en elektriese voer- tuie. As gevolg van die eienskappe van hierdie ysterlose ongespletepoolmasjien kan net tru-EMK-metodes gebruik word om die rotorposisie sensorloos te bepaal. Hierdie tru- EMK-metodes kan nie die rotorposisie by rotorstilstand en lae rotasiespoed akkuraat afskat nie. By toepassings waar e ektiwiteit by lae spoed baie belangrik is, is 'n rotorpo- sisiesensor by lae spoed gebruik wat die rotorposisie afskat deur die magnetiese spreivelde agter die Halbach- permanentemagneetstruktuur te ontleed. Die beheerstelsel en die posi- sieafskatter vereis akkurate stelselparameters. 'n Ooplusparameteridenti kasiealgoritme is gebruik om al vyf stelselparameters af te skat sodra die stelsel aangeskakel word. 'n Geslotelusparameterafskatter verfyn dan die parameters verder. 'n Demonstrasiemodel is ontwikkel om die gesloteluskombinasie van al die elemente te demonstreer. Die gedoku- menteerde resultate bewys dat hierdie masjien saam met die stelselelemente in sensorlose motor sowel as opwekkertoepassings gebruik kan word.

Advisors/Committee Members: Strauss, Johan, Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering..

Subjects/Keywords: UCTD; Permanent magnets – Sensors; Synchronization; Rotational motion

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APA (6^th Edition):

Treurnicht, A. (2017). Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/101217

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Treurnicht, Anton. “Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling.” 2017. Thesis, Stellenbosch University. Accessed March 01, 2021. http://hdl.handle.net/10019.1/101217.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Treurnicht, Anton. “Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling.” 2017. Web. 01 Mar 2021.

Vancouver:

Treurnicht A. Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling. [Internet] [Thesis]. Stellenbosch University; 2017. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10019.1/101217.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Treurnicht A. Sensorless control of an ironless permanent magnet synchronous machine with automatic machine modelling. [Thesis]. Stellenbosch University; 2017. Available from: http://hdl.handle.net/10019.1/101217

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Delaware

16. Mahfouzi, Farzad. Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions.

Degree: PhD, University of Delaware, Department of Physics and Astronomy, 2014, University of Delaware

URL: http://udspace.udel.edu/handle/19716/16765

► Current and future technological needs increasingly motivate the intensive scientific research of the properties of materials at the nano-scale. One of the most important domains… (more)

▼ Current and future technological needs increasingly motivate the intensive scientific research of the properties of materials at the nano-scale. One of the most important domains in this respect at present concerns nano-electronics and its diverse applications. The great interest in this domain arises from the potential reduction of the size of the circuit components, maintaining their quality and functionality, and aiming at greater efficiency, economy, and storage characteristics for the corresponding physical devices. The aim of this thesis is to present a contribution to the analysis of the electronic charge and spin transport phenomena that occur at the quantum level in nano-structures. This thesis spans the areas of quantum transport theory through time-dependent systems, electron-boson interacting systems and systems of interest to spintronics. A common thread in the thesis is to develop the theoretical foundations and computational algorithms to numerically simulate such systems. In order to optimize the numerical calculations I resort to different techniques (such as graph theory in finding inverse of a sparse matrix, adaptive grids for integrations and programming languages ({\it e.g.,} MATLAB and C++) and distributed computing tools (MPI, CUDA). Outline of the Thesis: After giving an introduction to the topics covered in this thesis in Chapter 1, I present the theoretical foundations to the field of non-equilibrium quantum statistics in Chapter 2. The applications of this formalism and the results are covered in the subsequent chapters as follows: Spin and charge quantum pumping in time-dependent systems: Covered in Chapters 3, 4 and 5, this topics was initially motivated by experiments on measuring voltage signal from a magnetic tunnel junction (MTJ) exposed to a microwave radiation in ferromagnetic resonance (FMR) condition. In Chapter 3 we found a possible explanation for the finite voltage signal measured from a tunnel junction consisting of only a single ferromagnet (FM). I show that this could be due to the existence of Rashba spin-orbit coupling (SOC) at the interface of the FM and insulator. Assuming that the measured signals are quantum mechanical effect where a solution to the time dependent Schrodinger equation is required, I use Keldysh Green function formalism to introduce a "multi-photon" approach which takes into account the effects of time-dependent term exactly up to scatterings from a finite number of photons. We then proceed to find the corresponding Green function numerically using a recursive method which allows us to increase the size of the system significantly. We also implement other approximations such as adiabatic and rotating frame approaches and compared them with our approach. In Chapter 4, I investigate the spin and charge pumping from a precessing magnetization attached to the edge of a 2-dimensional topological insulator (2DTI). We show that, in this system a huge spin current (or voltage signal if the FM covers only one edge) can be pumped for very small cone angles of the… Advisors/Committee Members: Nikolic, Branislav.

Subjects/Keywords: Tunneling (Physics); Heterostructures.; Magnets.; Transport theory.; Spintronics.

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APA (6^th Edition):

Mahfouzi, F. (2014). Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions. (Doctoral Dissertation). University of Delaware. Retrieved from http://udspace.udel.edu/handle/19716/16765

Chicago Manual of Style (16^th Edition):

Mahfouzi, Farzad. “Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions.” 2014. Doctoral Dissertation, University of Delaware. Accessed March 01, 2021. http://udspace.udel.edu/handle/19716/16765.

MLA Handbook (7^th Edition):

Mahfouzi, Farzad. “Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions.” 2014. Web. 01 Mar 2021.

Vancouver:

Mahfouzi F. Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions. [Internet] [Doctoral dissertation]. University of Delaware; 2014. [cited 2021 Mar 01]. Available from: http://udspace.udel.edu/handle/19716/16765.

Council of Science Editors:

Mahfouzi F. Nonequilibrium green function approach to elastic and inelastic spin-charge transport in topological insulator-based heterostructures and magnetic tunnel junctions. [Doctoral Dissertation]. University of Delaware; 2014. Available from: http://udspace.udel.edu/handle/19716/16765

Columbia University

17. Liu, Lian. μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃.

Degree: 2016, Columbia University

URL: https://doi.org/10.7916/D82F7ND1

► A skyrmion is a vortex-like spin pattern which has been observed in so-called B20 magnetic systems such as MnSi, (Mn,Fe)Si and a few other metallic… (more)

▼ A skyrmion is a vortex-like spin pattern which has been observed in so-called B20 magnetic systems such as MnSi, (Mn,Fe)Si and a few other metallic magnets as well as in insulating Cu₂OSeO₃. We conduct a comprehensive study of muon spin relaxation (μSR) on bulk single crystals of MnSi and (Mn,Fe)Si, a MBE thin film of MnSi, and a ceramic specimen of Cu₂OSeO₃ in this work. The generic second-order like phase transition indicated by 1/T₁ peaks at T_c in bulk systems is discussed in light of the Brazovskii-type first-order phase transition due to the presence of the DM interaction. We also discuss the different temperature dependences of μ⁺ spin-lattice relaxation rate 1/T₁ in bulk pure systems MnSi and Cu₂OSeO₃ and their commonalities in the paramagnetic state and the ordered state due to the DM interaction. Furthermore, we highlight the enhanced 1/T₁ in the skyrmion crystal (SkX) phase compared to neighboring conical phases due to an abundance of low-energy magnetic fluctuations/excitations. This abundance is corroborated by the reduced static order parameter in the SkX phase of MnSi compared to neighboring conical phases, deduced by combining μSR experiments and magnetic field simulations. The intermediate (IM) region above T_c, where the modification of magnetic transition by the DM interaction starts to appear in MnSi, exhibit multi-time scale spin fluctuations, topologically non-trivial Hall resistivity and non-Fermi-liquid exponent of longitudinal resistivity in single-crystal Mn₀.₉Fe₀.₁Si and the MnSi MBE thin film, similar to the magnetically disordered phase of pure MnSi under hydrostatic pressure. These three defining features indicate a fluctuating skyrmion liquid in this magnetically ordered state, stabilized by pressure, disorder or reduced dimensionality. Moreover, the magnetic transition is strongly first order in the MnSi MBE thin film sample, different from the Brazovskii-type weakly first order transition in bulk samples, suggesting the importance of reduced dimensionality in modifying the nature of magnetic phase transitions in B20 systems.

Subjects/Keywords: Condensed matter; Magnets; Magnetism; Skyrme model; Physics

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APA (6^th Edition):

Liu, L. (2016). μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/D82F7ND1

Chicago Manual of Style (16^th Edition):

Liu, Lian. “μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃.” 2016. Doctoral Dissertation, Columbia University. Accessed March 01, 2021. https://doi.org/10.7916/D82F7ND1.

MLA Handbook (7^th Edition):

Liu, Lian. “μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃.” 2016. Web. 01 Mar 2021.

Vancouver:

Liu L. μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃. [Internet] [Doctoral dissertation]. Columbia University; 2016. [cited 2021 Mar 01]. Available from: https://doi.org/10.7916/D82F7ND1.

Council of Science Editors:

Liu L. μSR Study of B20 Magnetic Systems: MnSi, Mn₀.₉Fe₀.₁Si and Cu₂OSeO₃. [Doctoral Dissertation]. Columbia University; 2016. Available from: https://doi.org/10.7916/D82F7ND1

Uppsala University

18. Stangel, Anders. Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials.

Degree: Materials Theory, 2016, Uppsala University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301992

► The magnetic properties of the (FexNi1-x)2B family of materials are explored using DFT calculations utilizing the FPLO and SPR-KKR code packages. It is found… (more)

Subjects/Keywords: Magnetocrystalline anisotropy; magnetism; DFT; permanent magnets

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APA (6^th Edition):

Stangel, A. (2016). Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials. (Thesis). Uppsala University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301992

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Stangel, Anders. “Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials.” 2016. Thesis, Uppsala University. Accessed March 01, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301992.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Stangel, Anders. “Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials.” 2016. Web. 01 Mar 2021.

Vancouver:

Stangel A. Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials. [Internet] [Thesis]. Uppsala University; 2016. [cited 2021 Mar 01]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301992.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Stangel A. Magnetocrystalline Anisotropy in(FexNi1-x)2B Materials. [Thesis]. Uppsala University; 2016. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301992

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Victoria

19. Rowe, Andrew Michael. Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions.

Degree: Department of Mechanical Engineering, 2018, University of Victoria

URL: https://dspace.library.uvic.ca//handle/1828/10248

► A technology that has the potential to liquefy hydrogen and natural gas efficiently is an Active Magnetic Regenerative Liquefier (AMRL). An AMRL exploits the magnetocaloric… (more)

Subjects/Keywords: Refrigerants; Superconducting magnets; Regenerators; Phase transitions

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APA (6^th Edition):

Rowe, A. M. (2018). Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/10248

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rowe, Andrew Michael. “Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions.” 2018. Thesis, University of Victoria. Accessed March 01, 2021. https://dspace.library.uvic.ca//handle/1828/10248.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rowe, Andrew Michael. “Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions.” 2018. Web. 01 Mar 2021.

Vancouver:

Rowe AM. Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions. [Internet] [Thesis]. University of Victoria; 2018. [cited 2021 Mar 01]. Available from: https://dspace.library.uvic.ca//handle/1828/10248.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rowe AM. Active magnetic regenerators: performance in the vicinity of para-ferromagnetic second order phase transitions. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/10248

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan State University

20. Kim, Jong-Won. An eight tesla superconducting magnet for cyclotron studies.

Degree: PhD, Department of Physics and Astronomy, 1994, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:24033

Subjects/Keywords: Superconducting magnets; Cyclotrons

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APA (6^th Edition):

Kim, J. (1994). An eight tesla superconducting magnet for cyclotron studies. (Doctoral Dissertation). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:24033

Chicago Manual of Style (16^th Edition):

Kim, Jong-Won. “An eight tesla superconducting magnet for cyclotron studies.” 1994. Doctoral Dissertation, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:24033.

MLA Handbook (7^th Edition):

Kim, Jong-Won. “An eight tesla superconducting magnet for cyclotron studies.” 1994. Web. 01 Mar 2021.

Vancouver:

Kim J. An eight tesla superconducting magnet for cyclotron studies. [Internet] [Doctoral dissertation]. Michigan State University; 1994. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:24033.

Council of Science Editors:

Kim J. An eight tesla superconducting magnet for cyclotron studies. [Doctoral Dissertation]. Michigan State University; 1994. Available from: http://etd.lib.msu.edu/islandora/object/etd:24033

Michigan State University

21. Berg, Richard Eugene. Magnetic coil design for a superconducting air-cored 40-mev cyclotron.

Degree: MS, Dept. of Physics and Astronomy, 1963, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:8229

Subjects/Keywords: Superconducting magnets; Cyclotrons

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APA (6^th Edition):

Berg, R. E. (1963). Magnetic coil design for a superconducting air-cored 40-mev cyclotron. (Masters Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:8229

Chicago Manual of Style (16^th Edition):

Berg, Richard Eugene. “Magnetic coil design for a superconducting air-cored 40-mev cyclotron.” 1963. Masters Thesis, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:8229.

MLA Handbook (7^th Edition):

Berg, Richard Eugene. “Magnetic coil design for a superconducting air-cored 40-mev cyclotron.” 1963. Web. 01 Mar 2021.

Vancouver:

Berg RE. Magnetic coil design for a superconducting air-cored 40-mev cyclotron. [Internet] [Masters thesis]. Michigan State University; 1963. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:8229.

Council of Science Editors:

Berg RE. Magnetic coil design for a superconducting air-cored 40-mev cyclotron. [Masters Thesis]. Michigan State University; 1963. Available from: http://etd.lib.msu.edu/islandora/object/etd:8229

Michigan State University

22. Zhang, Bo. Characteristics of the superconducting magnets for the S800 spectrometer.

Degree: PhD, Department of Physics and Astronomy, 1997, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:26581

Subjects/Keywords: Superconducting magnets; Spectrometer

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APA (6^th Edition):

Zhang, B. (1997). Characteristics of the superconducting magnets for the S800 spectrometer. (Doctoral Dissertation). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:26581

Chicago Manual of Style (16^th Edition):

Zhang, Bo. “Characteristics of the superconducting magnets for the S800 spectrometer.” 1997. Doctoral Dissertation, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:26581.

MLA Handbook (7^th Edition):

Zhang, Bo. “Characteristics of the superconducting magnets for the S800 spectrometer.” 1997. Web. 01 Mar 2021.

Vancouver:

Zhang B. Characteristics of the superconducting magnets for the S800 spectrometer. [Internet] [Doctoral dissertation]. Michigan State University; 1997. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:26581.

Council of Science Editors:

Zhang B. Characteristics of the superconducting magnets for the S800 spectrometer. [Doctoral Dissertation]. Michigan State University; 1997. Available from: http://etd.lib.msu.edu/islandora/object/etd:26581

University of Illinois – Urbana-Champaign

23. Liu, Yun. Magnetization dynamics of single molecule magnets.

Degree: PhD, 0240, 2014, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/50725

► Molecular magnets are a class of magneto-organic material which behave at low temperatures like a single quantum spin of large angular momentum. In this thesis… (more)

Subjects/Keywords: molecular magnets; spin path integrals; quantum mechanics

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APA (6^th Edition):

Liu, Y. (2014). Magnetization dynamics of single molecule magnets. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/50725

Chicago Manual of Style (16^th Edition):

Liu, Yun. “Magnetization dynamics of single molecule magnets.” 2014. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 01, 2021. http://hdl.handle.net/2142/50725.

MLA Handbook (7^th Edition):

Liu, Yun. “Magnetization dynamics of single molecule magnets.” 2014. Web. 01 Mar 2021.

Vancouver:

Liu Y. Magnetization dynamics of single molecule magnets. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2014. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/2142/50725.

Council of Science Editors:

Liu Y. Magnetization dynamics of single molecule magnets. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/50725

University of Melbourne

24. Huang, Haibei. Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate.

Degree: 2018, University of Melbourne

URL: http://hdl.handle.net/11343/214488

► We have theoretically and computationally investigated the magnetic interaction between the Ln III Pc 2 (Ln=Tb, Dy, Ho and Er; Pc=dianion of phthalocyanine) molecule and… (more)

▼ We have theoretically and computationally investigated the magnetic interaction between the Ln III Pc 2 (Ln=Tb, Dy, Ho and Er; Pc=dianion of phthalocyanine) molecule and a Ni(111) substrate, via the simulation of X-ray Magnetic Circular Dichroism (XMCD) experiments for two systems: LnPc2 /Ni(111) and TbPc2 /graphene/Ni(111). We have thus developed ab initio parameterized effective spin Hamiltonians having as a sole fitting parameter the magnetic coupling to the experimental magnetization of the Ni(111) substrate. Simulation of experimental data via our Hamiltonians allowed us to extract the following information about the molecule-surface coupling: (i) the Ln-Ni(111) effective coupling is antiferromagnetic; (ii) the Ln-Ni(111) strength of effective coupling decreases in the order Ln=Tb, Dy, Er; (iii) the details of the effects of magnetic anisotropy on the XMCD experimental magnetization can only be explained either by assuming a hugely anisotropic coupling mechanism, or by explicitly considering the role of a radical delocalized on two separate Pc ligands in the relevant electronic states, i.e. assuming the molecule on the surface remains close to the [LnPc2]⁰ oxidation state as before in situ ultra-high vacuum (UHV) deposition on Ni(111). Based on our simulations, it is argued that the Pc2 radical not only mediates the Ln-Ni(111) coupling, but also appears to influence the Ln-based magnetic moment observed via XMCD. While we could not achieve a clear cut identification of the signature of the Pc2 radical in the XMCD experiments, our studies indicate that the radical Pc2 ligand plays an important role in the communication between the 4f-electrons and magnetic substrates. Hence, we also performed a detailed ab initio CASSCF/RASSCF-RASSI-SO study of the intra-molecular exchange coupling between 4f-electrons and Pc2 radical ligand in [LnPc2]⁰ . We found that the overall coupling is ferromagnetic, consistent with our simulation of XMCD experiments, and especially with recent Electron Paramagnetic Resonance (EPR) results, although the ferromagnetic coupling is greatly overestimated at the CASSCF level of theory; We also found that a more accurate predictions of this ferromagnetic coupling can be achieved if accounting for spin-polarization effects via extended active spaces at the RASSCF level of theory.

Subjects/Keywords: lanthanides; single molecule magnets; ab-initio

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APA (6^th Edition):

Huang, H. (2018). Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/214488

Chicago Manual of Style (16^th Edition):

Huang, Haibei. “Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate.” 2018. Doctoral Dissertation, University of Melbourne. Accessed March 01, 2021. http://hdl.handle.net/11343/214488.

MLA Handbook (7^th Edition):

Huang, Haibei. “Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate.” 2018. Web. 01 Mar 2021.

Vancouver:

Huang H. Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate. [Internet] [Doctoral dissertation]. University of Melbourne; 2018. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/11343/214488.

Council of Science Editors:

Huang H. Magnetic interactions between lanthanide single molecule magnets and a magnetic substrate. [Doctoral Dissertation]. University of Melbourne; 2018. Available from: http://hdl.handle.net/11343/214488

University of Hong Kong

25. Dias, Andrew Paul Lakshman Henry. Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias.

Degree: 1999, University of Hong Kong

URL: http://hdl.handle.net/10722/33271

Subjects/Keywords: Magnets.; Dental materials.

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APA (6^th Edition):

Dias, A. P. L. H. (1999). Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/33271

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dias, Andrew Paul Lakshman Henry. “Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias.” 1999. Thesis, University of Hong Kong. Accessed March 01, 2021. http://hdl.handle.net/10722/33271.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dias, Andrew Paul Lakshman Henry. “Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias.” 1999. Web. 01 Mar 2021.

Vancouver:

Dias APLH. Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias. [Internet] [Thesis]. University of Hong Kong; 1999. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10722/33271.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dias APLH. Aspects of the use and design of magnets in dentistry: y Andrew PaulLakshman Henry Dias. [Thesis]. University of Hong Kong; 1999. Available from: http://hdl.handle.net/10722/33271

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona

26. DAMENTO, MICHAEL ANTHONY. DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE.

Degree: 1986, University of Arizona

URL: http://hdl.handle.net/10150/183945

► Magnetization processes in a sintered Nd-Fe-B permanent magnet (NEOMAX-35) were examined on a small scale using a Hall-effect microprobe with an active area 75 μm… (more)

Subjects/Keywords: Permanent magnets.; Magnetism.

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APA (6^th Edition):

DAMENTO, M. A. (1986). DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/183945

Chicago Manual of Style (16^th Edition):

DAMENTO, MICHAEL ANTHONY. “DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE. ” 1986. Doctoral Dissertation, University of Arizona. Accessed March 01, 2021. http://hdl.handle.net/10150/183945.

MLA Handbook (7^th Edition):

DAMENTO, MICHAEL ANTHONY. “DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE. ” 1986. Web. 01 Mar 2021.

Vancouver:

DAMENTO MA. DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE. [Internet] [Doctoral dissertation]. University of Arizona; 1986. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10150/183945.

Council of Science Editors:

DAMENTO MA. DETECTION OF MAGNETIZATION REVERSAL IN A NEODYMIUM-IRON-BORON MAGNET USING A HALL-EFFECT MICROPROBE. [Doctoral Dissertation]. University of Arizona; 1986. Available from: http://hdl.handle.net/10150/183945

University of Tennessee – Knoxville

27. Ghimire, Nirmal Jeevi. Complex magnetism in noncentrosymmetric magnets.

Degree: 2013, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/2427

► Broken inversion symmetry in a crystal lattice allows an extra term called the Dzyaloshinskii-Moriya (DM) interaction in the magnetic Hamiltonian. The DM interaction tends to… (more)

▼ Broken inversion symmetry in a crystal lattice allows an extra term called the Dzyaloshinskii-Moriya (DM) interaction in the magnetic Hamiltonian. The DM interaction tends to align spins in perpendicular orientation and therefore competes with the exchange interaction that favors collinear spins. This competition results in different modulated chiral magnetic structures depending on the relative strength of the two interactions. Skyrmion, soliton and magnetic blue phases are some of the anticipated structures. This dissertation extends the search for these exotic magnetic structures using various techniques to study the magnetism in the noncentrosymmetric magnets Cr11Ge19 [chromium eleven germanium nineteen], Cr1/3NbS2 [chromium one-third niobium disulphide] and K2V3O8 [fresnoite-type potassium vanadate]. Experimental investigations of magnetic, thermal, structural and elastic properties of Cr11Ge19 indicate complex itinerant ferromagnetism, evidence of spin wave excitations, and strong magnetoelastic coupling in this material. First principles calculations support the presence of itinerant ferromagnetism and suggest a noncollinear ground state may be expected. In the chiral helimagnet Cr1/3NbS2 the magnetic transition is found to strongly affect the electrical transport. Spin reorientation from the helimagnetic ground state to the commensurate ferromagnetic state is evident in the magnetoresistance. Neutron scattering is used to demonstrate the change in the periodicity of the incommensurate structure and the eventual incommensurate to commensurate transition, in accordance with the theoretical prediction of the soliton model. The tetragonal easy axis antiferromagnet K2V3O8 has been investigated by DC magnetization, AC susceptibility and heat capacity measurements. Based on the comparison of the behaviors observed in these measurements with other well-studied chiral helimagnets, the existence of two different spiral structures - one parallel and one perpendicular to the c axis - is proposed.

Subjects/Keywords: Noncentrosymmetric magnets; soliton; skyrmion; Condensed Matter Physics

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APA (6^th Edition):

Ghimire, N. J. (2013). Complex magnetism in noncentrosymmetric magnets. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/2427

Chicago Manual of Style (16^th Edition):

Ghimire, Nirmal Jeevi. “Complex magnetism in noncentrosymmetric magnets.” 2013. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed March 01, 2021. https://trace.tennessee.edu/utk_graddiss/2427.

MLA Handbook (7^th Edition):

Ghimire, Nirmal Jeevi. “Complex magnetism in noncentrosymmetric magnets.” 2013. Web. 01 Mar 2021.

Vancouver:

Ghimire NJ. Complex magnetism in noncentrosymmetric magnets. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2013. [cited 2021 Mar 01]. Available from: https://trace.tennessee.edu/utk_graddiss/2427.

Council of Science Editors:

Ghimire NJ. Complex magnetism in noncentrosymmetric magnets. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2013. Available from: https://trace.tennessee.edu/utk_graddiss/2427

Massey University

28. Walsh, Rowan Martin. High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand .

Degree: 2011, Massey University

URL: http://hdl.handle.net/10179/3505

► Electromagnets play an important role in everyday life from motors and generators to such devices as Magnetic Resonance Imaging (MRI). The larger a magnetic field… (more)

▼ Electromagnets play an important role in everyday life from motors and generators to such devices as Magnetic Resonance Imaging (MRI). The larger a magnetic field needed in such a device the more demand there is in power consumption and space. The development of superconductors (SC) and their ability to dissipate negligible power has made it possible to create larger fields in a more cost effective and space efficient manner. The disadvantage of the SC is that it needs to be operated at cryogenic temperatures (typically below 110 K). Cryogenics is a significant cost factor so the less power needed for cooling a SC magnet the more cost effective the system can become. The main heat load comes from the ohmic dissipation of the current leads necessary to energise the magnet. The current leads provide the electrical connection from the power supply at room temperature to the coils in the cryogenic environment. To circumnavigate this heat load a superconducting device known as a flux pump (FP) can be embedded in the cryogenic environment. The flux pump operation can be generalised as a DC generator, which minimises ohmic heating and makes the power supply needed to energise the magnet superfluous. HTS 110 is a magnet manufacturer who has assigned the task of implementing a flux pump into a commercial magnet application and developing a complete system capable of controlling a homogenous current level in their magnets. Such a flux pump module was developed and successfully incorporated into an existing SC magnet. This thesis details the mechanical design, control hardware, required software used to create this technology and the benefits it presents. Compared to the current lead technology, the developed flux pump module reduced the heat load on the cryo-cooler by almost a factor of 5. In addition a produced magnetic field of 750 mT was achieved, which corresponds to a current of 68 A in the magnet coils. Such a high field could not have been obtained in the present setup with conventional technology. The large heat load caused by current leads would increase the overall temperature of the coils and in turn decrease the current capability of the circuit to approximately 20 A, resulting in a field that is more than three times smaller. A full control system using field strength as feedback to control the rotation of the FP was implemented. This included an iterative hardware design and fabrication process followed by software implementation, that led to a high level system encompassing a PID type control algorithm. The control system achieved a field stability of 30 parts per million (PPM) which puts the system in reach for the needed NMR stability criterion of 1 PPM.

Subjects/Keywords: Superconducting magnets; Heat load; Flux pump; Electromagnets

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APA (6^th Edition):

Walsh, R. M. (2011). High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand . (Thesis). Massey University. Retrieved from http://hdl.handle.net/10179/3505

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Walsh, Rowan Martin. “High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand .” 2011. Thesis, Massey University. Accessed March 01, 2021. http://hdl.handle.net/10179/3505.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Walsh, Rowan Martin. “High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand .” 2011. Web. 01 Mar 2021.

Vancouver:

Walsh RM. High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand . [Internet] [Thesis]. Massey University; 2011. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10179/3505.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Walsh RM. High temperature superconducting flux pump : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand . [Thesis]. Massey University; 2011. Available from: http://hdl.handle.net/10179/3505

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan State University

29. Zaheer, Muhammad Jawad. Tool for quality testing of raw material of permanent magnets.

Degree: 2012, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:419

►

Thesis M.S. Michigan State University. Electrical Engineering 2012.

Permanent magnets are used extensively in synchronous machines that produce high power density, wide speed range and… (more)

▼

Thesis M.S. Michigan State University. Electrical Engineering 2012.

Permanent magnets are used extensively in synchronous machines that produce high power density, wide speed range and high efficiency. It is important therefore to determine the qualityof the magnetic material before the assembly and magnetization in the electrical machines.Once they are installed, they cannot be removed. Thus, if the quality of the magnets is inadequate, the rotor assembly is unusable.In this thesis, different types of magnetometers are reviewed before pulsed field magnetometer system is chosen due to its simplicity, quick and smaller size to measure the magnetic hysteresis for characterization. A pulsed magnetometer is useful for testing high performance magnets due to their ability to produce magnetic fields, high enough to saturate the rare earth permanent magnets. The basic geometry, coil winding configuration and input currents of the pulsed field magnetometer are calculated using Finite Element Method andMATLAB/Simulink. The whole coil arrangement combined with power electronic circuitry is designed and built. The control is implemented using LabView and the results are post processed using MATLAB.The first part of the work is to plot the measured hysteresis loop using two current pulses with magnet position at 0° and 180° at different temperatures after compensating for open-loop demagnetization factor. Three different Neodymium-Iron-Boron magnets: Nickel plated,Aluminum coated and Black painted magnets are used for this test.The second part of the work is to distinguish between good and bad raw material of the permanent magnets used in PMAC machines. For this, the magnetic field is applied to good raw material magnet such that the negative peak forces the magnet operating point to fall slightlyabove or close to the knee of the hysteresis curve. It is used as reference and compared to the magnets with some amount of impurities. The magnets with bad raw material trail different minor loops and recoil line when compared to the magnets with good raw material.On the whole, the pulsed field magnetometer, coupled with minor loops and recoil lines, is used as a successful technique to distinguish between good and bad raw material of the permanent magnets used in PMAC machines.

Description based on online resource; title from PDF t.p. (ProQuest, viewed Dec. 4, 2013)

Advisors/Committee Members: Strangas, Elias, Wang, Bingsen, Rothwell, Edward.

Subjects/Keywords: Permanent magnets – Design and construction; Electrical engineering

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APA (6^th Edition):

Zaheer, M. J. (2012). Tool for quality testing of raw material of permanent magnets. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:419

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zaheer, Muhammad Jawad. “Tool for quality testing of raw material of permanent magnets.” 2012. Thesis, Michigan State University. Accessed March 01, 2021. http://etd.lib.msu.edu/islandora/object/etd:419.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zaheer, Muhammad Jawad. “Tool for quality testing of raw material of permanent magnets.” 2012. Web. 01 Mar 2021.

Vancouver:

Zaheer MJ. Tool for quality testing of raw material of permanent magnets. [Internet] [Thesis]. Michigan State University; 2012. [cited 2021 Mar 01]. Available from: http://etd.lib.msu.edu/islandora/object/etd:419.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zaheer MJ. Tool for quality testing of raw material of permanent magnets. [Thesis]. Michigan State University; 2012. Available from: http://etd.lib.msu.edu/islandora/object/etd:419

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

30. Mendes Neto, Teofilo. Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas.

Degree: PhD, Tecnologia Nuclear - Materiais, 2011, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/85/85134/tde-28092011-094845/ ;

►

Neste estudo, as propriedades magnéticas dos ímãs sinterizados, produzidos a partir de uma mistura de ligas Pr16Fe76B8 e Pr14FebalCo16B6Nb0,1Mx, onde M= Al, Cu, P, Si,… (more)

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Neste estudo, as propriedades magnéticas dos ímãs sinterizados, produzidos a partir de uma mistura de ligas Pr16Fe76B8 e Pr14FebalCo16B6Nb0,1Mx, onde M= Al, Cu, P, Si, Gd, Ga, Dy, Tb e x= 0,1, 0,3, 0,5 % at. em iguais proporções, foram correlacionadas com as características microestruturais através de microscopia eletrônica de varredura (MEV) e de transmissão (MET). Utilizou-se microscopia eletrônica de varredura (MEV) e processamento computacional das micrografias, na investigação das características associadas ao tamanho e formato dos grãos magnéticos (Φ). A correlação utilizada indicou que fatores de quadratura superiores estão associados a grãos mais arredondados e com distribuição de tamanho mais estreita. Considerando que a variação no tamanho de grão e os valores de coercividade não se mostraram conclusivas com MEV, utilizou-se o recurso da microscopia eletrônica de transmissão (MET), microanálise com EDS e padrão de difração eletrônica. A associação da coercividade com a microestrutura foi feita com base nas investigações das fases não magnéticas, ricas em praseodímio dos pontos triplos e nos contornos de grãos. Com o microscópio de transmissão de alta resolução (HRTEM), foi possível observar a presença de uma camada contínua e regular entre os grãos da fase magnética para o ímã com adição de Ga 0,25% at. A modificação da microestrutura no contorno de grão do ímã com adição de Ga pode ser indicada como responsável pelo aumento de 10% na coercividade (1100 mT) comparado com o ímã Pr15FebalCo8B7Nb0,05.

In this study the magnetic properties of sintered magnets, prepared with a mixture of Pr16Fe76B8 and Pr14FebalCo16B6Nb0.1Mx alloys, where M = Al, Cu, P, Si, Gd, Ga, Dy, Tb and x = 0.1, 0.3, 0.5 at.% in the same proportions, were correlated with the microstructural features by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM and computer processing of the micrographs were used in order to provide the characteristics associated with the size and shape of the magnetic grains (Φ phase). The correlation used shows that superior squareness factors are associated with rounder and narrower size distribution grains. Considering that the variation in the grain size and coercivity values were not conclusive with SEM, it has been used TEM, micro analysis by EDS and electron diffraction pattern. The coercivity relation with the microstructure was based on investigations of non-magnetic phases, in triple points, and in the grain boundary. With a high resolution transmission microscope (HRTEM), it was possible to observe a regular and continuous layer between the grains of the magnetic phase for the magnet with 0.25 at.% of Ga. The presence of such boundary can be indicated as responsible for higher coercivity values of this magnet. Microstructure was modified in the grain boundary by Ga addition and can be indicated as responsible for coercivity value (1100 mT) 10% higher than Pr15FebalCo8B7Nb0.05 magnet.

Advisors/Committee Members: Takiishi, Hidetoshi.

Subjects/Keywords: ímãs permanentes; ímãs sinterizados; NdFeB; NdFeB; permanent magnets; PrFeB; PrFeB; sintered magnets

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APA (6^th Edition):

Mendes Neto, T. (2011). Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/85/85134/tde-28092011-094845/ ;

Chicago Manual of Style (16^th Edition):

Mendes Neto, Teofilo. “Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas.” 2011. Doctoral Dissertation, University of São Paulo. Accessed March 01, 2021. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-28092011-094845/ ;.

MLA Handbook (7^th Edition):

Mendes Neto, Teofilo. “Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas.” 2011. Web. 01 Mar 2021.

Vancouver:

Mendes Neto T. Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas. [Internet] [Doctoral dissertation]. University of São Paulo; 2011. [cited 2021 Mar 01]. Available from: http://www.teses.usp.br/teses/disponiveis/85/85134/tde-28092011-094845/ ;.

Council of Science Editors:

Mendes Neto T. Estudo microestrutural e propriedades magnéticas em ímãs permanentes sinterizados a base de PrFeCoBNb com adições de elementos de ligas. [Doctoral Dissertation]. University of São Paulo; 2011. Available from: http://www.teses.usp.br/teses/disponiveis/85/85134/tde-28092011-094845/ ;

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