subject:(Kondo Insulator)

1. Hu, Rongwei. Investigation of a d-electron Kondo insulator FeSb2.

Degree: PhD, Physics, 2009, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:185/

► FeSb2 is a narrow band semiconductor, whose magnetic susceptibility strongly resembles that of FeSi, an archetype example of Kondo insulator. The unusual spectral weight transfer… (more)

▼ FeSb2 is a narrow band semiconductor, whose magnetic susceptibility strongly resembles that of FeSi, an archetype example of Kondo insulator. The unusual spectral weight transfer in the optical conductivity measurement and ab initio LDA+U calculations imply that FeSb2 is an unconventional semiconductor with strong electron correlations. In order to study the anisotropy and probe the electronic structure of FeSb2, single crystals are grown by high temperature flux method and carriers are introduced into FeSb2 by substituting Fe and Sb with Co/Cr and Te respectively. We investigated the magnetic and electrical properties of FeSb2 and the doping effects. Hall measurement on FeSb2 reveals that multiple band carriers with very large mobility difference are involved in the electrical transport. This can be explained by the orbital selective hybridization of the Fe d-orbitals with Sb-p electrons in FeSb2 involving only one electronic subsystem. Band structure calculation suggests that FeSb2 is close to a magnetic instability. Indeed, various magnetic orders are experimentally observed in doped FeSb2. For example, the activated Pauli paramagnetism of FeSb2 evolves into a weak ferromagnetism in Fe1-xCoxSb2 and a complex canted antiferromagnetic structure in Fe1-xCrxSb2 and Fe(Sb1-xTex)2. Metallic states are readily induced by doping FeSb2 as a result of band filling. Positive colossal magnetoresistance mainly attributed to quasi 1D weak localization is observed in Co doped FeSb2. With Te substitution, FeSb2 evolves from a strongly correlated semiconductor into a moderate heavy fermion metal. Most of the Kondo insulator materials are cubic, with the exception of CeRhSb and CeNiSn, and 4f intermetallics. An important question is that if the Kondo insulator scenario can be applied to 3d materials, e.g. FeSi and FeSb2. FeSb2 can be obtained in single crystal form with high quality and can be readily doped with carriers, thus it represents a model system with only 3d elements to study this physics. Our results indicate that the underling physics of FeSb2 can be well described by the Kondo insulator picture and FeSb2 resembles FeSi in many ways as a prototypical example of a nonrare-earth containing Kondo insulator. Advisors/Committee Members: Mitrovic, Vesna (director), Petrovic, Cedomir (director), Marston, Brad (reader), Valles, James (reader).

Subjects/Keywords: Kondo Insulator

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APA (6^th Edition):

Hu, R. (2009). Investigation of a d-electron Kondo insulator FeSb2. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:185/

Chicago Manual of Style (16^th Edition):

Hu, Rongwei. “Investigation of a d-electron Kondo insulator FeSb2.” 2009. Doctoral Dissertation, Brown University. Accessed January 26, 2021. https://repository.library.brown.edu/studio/item/bdr:185/.

MLA Handbook (7^th Edition):

Hu, Rongwei. “Investigation of a d-electron Kondo insulator FeSb2.” 2009. Web. 26 Jan 2021.

Vancouver:

Hu R. Investigation of a d-electron Kondo insulator FeSb2. [Internet] [Doctoral dissertation]. Brown University; 2009. [cited 2021 Jan 26]. Available from: https://repository.library.brown.edu/studio/item/bdr:185/.

Council of Science Editors:

Hu R. Investigation of a d-electron Kondo insulator FeSb2. [Doctoral Dissertation]. Brown University; 2009. Available from: https://repository.library.brown.edu/studio/item/bdr:185/

Rice University

2. Stavinoha, Macy L. Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds.

Degree: PhD, Natural Sciences, 2019, Rice University

URL: http://hdl.handle.net/1911/107802

► Magnetic and electronic correlations form the framework of physical properties observed in rare earth-based intermetallic compounds. Rare earth ions (La-Lu) can host a variety of… (more)

▼ Magnetic and electronic correlations form the framework of physical properties observed in rare earth-based intermetallic compounds. Rare earth ions (La-Lu) can host a variety of behaviors including the Kondo effect, crystal electric field splitting, long-range magnetic order, and valence fluctuations whose combined effects determine the ground state magnetic and electronic properties of the host intermetallic compound. In solid state chemistry and condensed matter physics disciplines, physical properties can be traced through structural families where these behaviors are common to the crystallographic arrangement of the compound. When changes in the physical properties are correlated with small changes in the chemical composition or crystallographic structure of the compound, this provides a route to study and tune the underlying quantum mechanical interactions responsible for unusual or useful characteristics of these materials. In this thesis, I will report the discovery of two new intermetallic compounds YbIr3Si7 and YbIr3Ge7 and two new substitutional series Eu(Ga1-xAlx)4 and Eu1-xAxGa4. The isostructural analogs YbIr3Si7 and YbIr3Ge7 differ greatly in their physical properties, and each compound is unique in its own respect. YbIr3Si7 shows a combination of behaviors that has not been reported in any other compound, including Kondo correlations, insulator-like resistivity, long-range magnetic order, and the onset of conductive surface states at low temperature. YbIr3Ge7, however, is a rare Kondo lattice ferromagnet and the first of which to crystallize in a rhombohedral crystal structure. In contrast, EuGa4 is an antiferromagnetic compound with a ubiquitous tetragonal crystal structure. Small changes in the magnetic Eu sublattice or the nonmagnetic Ga sublattice can introduce unexpected changes in the observed physical properties of the system. Here, Al substitution in the Ga sublattice to produce the single crystal series Eu(Ga1-xAlx)4 results in nonlinear changes to the magnetic ordering temperature and the presence of ferromagnetic correlations, despite the similar size and electronic con figuration of Al and Ga. In contrast, substitution in the magnetic Eu sublattice to form Eu1-xAxGa4 with A = Ca, La, or Sr shows that introducing the smaller Ca ion causes structural distortion, hole doping with La suppresses the ordering temperature rapidly, and Sr substitution slowly suppresses the magnetic order without sacrificing crystal quality. Advisors/Committee Members: Morosan, Emilia (advisor).

Subjects/Keywords: solid state chemistry; Kondo lattice; Kondo insulator

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APA (6^th Edition):

Stavinoha, M. L. (2019). Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/107802

Chicago Manual of Style (16^th Edition):

Stavinoha, Macy L. “Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds.” 2019. Doctoral Dissertation, Rice University. Accessed January 26, 2021. http://hdl.handle.net/1911/107802.

MLA Handbook (7^th Edition):

Stavinoha, Macy L. “Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds.” 2019. Web. 26 Jan 2021.

Vancouver:

Stavinoha ML. Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds. [Internet] [Doctoral dissertation]. Rice University; 2019. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1911/107802.

Council of Science Editors:

Stavinoha ML. Magnetic and Electronic Correlations in Rare Earth Intermetallic Compounds. [Doctoral Dissertation]. Rice University; 2019. Available from: http://hdl.handle.net/1911/107802

University of Illinois – Urbana-Champaign

3. Xin, Xianhao. Theoretical study of Kondo effect and related transport properties in topological insulator systems.

Degree: PhD, Physics, 2015, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/90450

► This thesis presents theoretical studies of the Kondo effect and related transport properties in topological insulator systems. The thesis mainly covers two topics: the Kondo… (more)

▼ This thesis presents theoretical studies of the Kondo effect and related transport properties in topological insulator systems. The thesis mainly covers two topics: the Kondo effect on the surface of a bulk topological insulator material and the Kondo effect in a topological insulator quantum dot. Other relevant background knowledge and theoretical techniques for the transport calculations are also discussed in the thesis. For the first topic, we investigate the role of magnetic impurities in the transport properties of a three dimensional topological insulator's surface states. First, we combine the second-order perturbation theory and the Boltzmann transport equation to calculate the magnetically induced resistivity in a topological insulator. Our result shows a non-perturbative behavior when conduction electrons and magnetic impurities' spins are antiferromagnetically coupled. The surface resistivity is found to display an oscillatory rather than isotropic behavior compared to the conventional Kondo effect. Both the variational method and renormalization group (RG) analysis are employed to compute the Kondo temperature, through which the non-perturbative behavior is confirmed. We further study the RG flows and demonstrate that the RG trajectories eventually flow into a strong coupling regime if the coupling is antiferromagnetic. This work is motivated by the recent transport experiments, in which surface currents were detected in topological insulators. The calculation is shown to be qualitatively consistent with the low temperature dip observed in the experimental R − T curve, and it might be one of the possible origins of the dip. For the second main topic, we investigate theoretically the nonequilibrium transport properties of a topological insulator quantum dot (TIQD) in the Coulomb blockade and Kondo regime. An Anderson impurity model is applied to a TIQD system coupled to two external leads, and we show that the model realizes the spin-orbital Kondo effect at the Dirac point where the edge states are not split by a finite-size effect, leading to an additional SU(4) symmetry because of the presence of strong mixture among four internal degrees of freedom. In a more realistic situation where the degeneracy is lifted due to the finite-size effect, we demonstrate that there is a richer structure in transport measurements. We illustrate a continuous crossover from four (spin and orbital) Coulomb peaks with large interpair spacing and small intrapair spacing to a double-peak structure in the local density of states (LDOS) as increasing the hybridization strength �� within the Coulomb blockade regime. When temperature falls below the Kondo temperature TK, four Kondo peaks show up in the nonequilibrium LDOS. Two of them are located at the chemical potential of each lead, and the other two are shifted away from the chemical potential by an amount proportional to the TIQD’s bare energy level, leading to a triple-peak structure in the differential conductance when a bias… Advisors/Committee Members: Stone, Michael (advisor), Hughes, Taylor L (Committee Chair), Cooper, Lance (committee member), Makins, Naomi C (committee member).

Subjects/Keywords: Topological Insulator; Kondo Effect; Transport

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APA (6^th Edition):

Xin, X. (2015). Theoretical study of Kondo effect and related transport properties in topological insulator systems. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/90450

Chicago Manual of Style (16^th Edition):

Xin, Xianhao. “Theoretical study of Kondo effect and related transport properties in topological insulator systems.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 26, 2021. http://hdl.handle.net/2142/90450.

MLA Handbook (7^th Edition):

Xin, Xianhao. “Theoretical study of Kondo effect and related transport properties in topological insulator systems.” 2015. Web. 26 Jan 2021.

Vancouver:

Xin X. Theoretical study of Kondo effect and related transport properties in topological insulator systems. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2142/90450.

Council of Science Editors:

Xin X. Theoretical study of Kondo effect and related transport properties in topological insulator systems. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/90450

4. Eo, Yun Suk. Surface and Bulk Transport of Samarium Hexaboride.

Degree: PhD, Physics, 2017, University of Michigan

URL: http://hdl.handle.net/2027.42/140918

► There has been a renewed interest in SmB6 during the past several years after the theoretical prediction that it is a topological Kondo insulator (TKI).… (more)

▼ There has been a renewed interest in SmB6 during the past several years after the theoretical prediction that it is a topological Kondo insulator (TKI). Soon after, the conducting surface was experimentally discovered, which is the key initial step for the TKI verication. Motivated by this work, this dissertation further studies both the surface and the bulk properties of SmB6 using electrical transport methods. To study the surface transport of SmB6, choosing the appropriate transport geometry is extremely important. A Corbino disk geometry, which confines the current path to a single surface, was used in this study. The measurements from the Corbino disk resulted in more physically acceptable values of carrier density than the results that were obtained from other conventional transport geometries. During this study, we also found that subsurface cracks that are created during surface preparation and domain boundaries of a polycrystal can provide unwanted conduction paths. After careful surface preparation, the magnetotransport was measured with an applied magnetic field of 34.5 T and a temperature of 0.3 K. A higher magnetic field was also applied up to 93 T, using the pulsed magnetic field, but Shubnikov de-Haas oscillations were not observed. Therefore, the strongest signatures needed to verify the nontrivial topology, such as the half-integer Landau index in the fan diagram have not yet been seen, nor were we able to find signatures of the three Fermi pockets predicted by theory. Instead, the Corbino disk magnetotransport results were consistent with the case when only one Fermi pocket exists. This can happen when the mobilities for each of the pockets are too small. From analyzing our magnetotransport, possible ranges of carrier density and mobility of each of the three Fermi pockets could be constructed in a 2D parameter space. When comparing with these Fermi pocket ranges that were constructed by magnetotransport to other experimental reports, only the angle-resolved photoemission spectroscopy reports are within the X-pocket range. To study the bulk of SmB6, a new transport method was invented, called the inverted resistance measurement. This inverted resistance measurement can be used for studying the bulk of SmB6 when the surface conduction dominates. By comparing the numerical simulation and the experimental measurement, the bulk resistivity was successfully extracted in the low-temperature range, where previously this was impossible due to the overwhelming surface conduction. Using this new method, we investigated the bulk of pure and disorder-induced SmB6 samples. We find that the bulk of SmB6 is an ideal insulator. The thermally activated behavior, with an activation energy of 4.01 meV, continues for ten orders of magnitude in resistivity. This thermally activated bulk behavior is found to be almost identical in the highly disordered SmB6 samples. These results suggest that the bulk of SmB6 has an energy gap that is free of impurity states, making the bulk transport remarkable. In addition to the… Advisors/Committee Members: Kurdak, Cagliyan (committee member), Zhong, Zhaohui (committee member), Allen, James W (committee member), Li, Lu (committee member), Sih, Vanessa (committee member), Sun, Kai (committee member).

Subjects/Keywords: Topological Kondo Insulator; Samarium Hexaboride; Physics; Science

…topological Kondo insulator (TKI). Soon after, the conducting surface was experimentally… …Kondo insulator after the early 1990s [22], and not only as a mixed-valent insulator… …rise by lowering the temperature is from a Kondo-like scattering mechanism. In the insulator… …Example of density states of an insulator and a metal. . . . . . Numerical simulation results of… …of SmB6 is an ideal insulator. The thermally activated behavior, with an activation energy…

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APA (6^th Edition):

Eo, Y. S. (2017). Surface and Bulk Transport of Samarium Hexaboride. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/140918

Chicago Manual of Style (16^th Edition):

Eo, Yun Suk. “Surface and Bulk Transport of Samarium Hexaboride.” 2017. Doctoral Dissertation, University of Michigan. Accessed January 26, 2021. http://hdl.handle.net/2027.42/140918.

MLA Handbook (7^th Edition):

Eo, Yun Suk. “Surface and Bulk Transport of Samarium Hexaboride.” 2017. Web. 26 Jan 2021.

Vancouver:

Eo YS. Surface and Bulk Transport of Samarium Hexaboride. [Internet] [Doctoral dissertation]. University of Michigan; 2017. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2027.42/140918.

Council of Science Editors:

Eo YS. Surface and Bulk Transport of Samarium Hexaboride. [Doctoral Dissertation]. University of Michigan; 2017. Available from: http://hdl.handle.net/2027.42/140918

University of California – Irvine

5. Stern, Alexander Lawrence. A novel approach to studying topological phases.

Degree: Physics, 2018, University of California – Irvine

URL: http://www.escholarship.org/uc/item/53h7w52r

► In the dissertation, I show some novel experimental techniques used to measure several exotic systems. A loop-less Sagnac interferometer is used to measure time reversal… (more)

Subjects/Keywords: Condensed matter physics; Chiral Majorana edge modes; Fraction quantum Hall effect; Sagnac interferometry; Topological Kondo insulator; Two-dimensional materials; Uniaxial strain

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APA (6^th Edition):

Stern, A. L. (2018). A novel approach to studying topological phases. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/53h7w52r

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):

Stern, Alexander Lawrence. “A novel approach to studying topological phases.” 2018. Thesis, University of California – Irvine. Accessed January 26, 2021. http://www.escholarship.org/uc/item/53h7w52r.

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

MLA Handbook (7^th Edition):

Stern, Alexander Lawrence. “A novel approach to studying topological phases.” 2018. Web. 26 Jan 2021.

Vancouver:

Stern AL. A novel approach to studying topological phases. [Internet] [Thesis]. University of California – Irvine; 2018. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/53h7w52r.

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

Council of Science Editors:

Stern AL. A novel approach to studying topological phases. [Thesis]. University of California – Irvine; 2018. Available from: http://www.escholarship.org/uc/item/53h7w52r

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

6. Hong, Seungmin. Renormalization for insulating states of matter.

Degree: PhD, 0240, 2013, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/44258

► In this thesis, we study three cases of insulating states of matter in terms of the renormalization procedure where the conventional renormalization group scheme is… (more)

▼ In this thesis, we study three cases of insulating states of matter in terms of the renormalization procedure where the conventional renormalization group scheme is not simply applicable. The first subject is the spectral weight structure of hole-doped Mott insulators. As the mixing between two separate Hubbard bands is dynamically generated, additional charge degrees of freedom is required to give a proper description to the relevant low-energy physics. On this account, we first discuss how the low-energy Hubbard band should be partitioned to account for the extra degrees of freedom. Following the exact integration procedure of the upper Hubbard band, we explicitly demonstrate that the conserved charge cannot be exhausted by counting quasiparticles. In addition, we argue that it is the existence of dynamically generated charge degrees of freedom that gives rise to the coexistence of poles and zeroes in the single-particle Green function. In comparison to the Fermi arc structure, which is intrinsic to cuperate phenomenology, we suggest that the suppression of the spectral weight at the back side of the arc is a consequence of composite excitations, arising from dynamical mixing. The second topic we study is the nature of the transition between two insulating states of matter in a weakly disordered bosonic system. In particular, we investigate the instabilities of the Mott-insulating phase within a renormalization group analysis of the replica field theory obtained by a strong-coupling expansion around the atomic limit. To this end, we identify a new order parameter and associated correlation length scale that are capable of capturing the transition from a state with zero compressibility, the Mott insulator, to another insulating state with finite compressibility, the Bose glass. The order parameter is the relative variance of the disorder-induced mass distribution. From its distinctive behavior on each phase, we find that the divergence of the relative variance in the Bose glass signals the breakdown of self-averaging. Lastly, we also emphasize that the transition at commensurate filling is governed by a different fixed point in the renormalization group flow. The last topic discussed is the thermoelectric properties of the correlated Kondo lattice system at low temperature. Specifically, we explore the periodic Anderson impurity model with spin-orbit interactions, using the slave-particle method. As the thermopower is related to the entropy per carrier, particle-hole asymmetry and a large density of states at the chemical potential make Kondo insulator an ideal platform for thermoelectrics. In this respect, we further explore the possibility to improve the thermoelectric performance by tuning the crystal electric field splitting, the spin-orbit interaction strength, and orbital degeneracy. Advisors/Committee Members: Phillips, Philip W. (advisor), Stone, Michael (Committee Chair), Phillips, Philip W. (committee member), Cooper, S. Lance (committee member), Leigh, Robert G. (committee member).

Subjects/Keywords: Renormalization; Hubbard model; Mott insulator; Bose glass; Kondo insulator

…1.2.1 Mott insulators . . . . . 1.2.2 Bose glass . . . . . . . . 1.2.3 Kondo insulator… …Bose glass. DOS Density of states. IR Infrared. KI Kondo insulator. LSCO La2−x Srx… …transport properties of multi-orbital Kondo insulator with spin-orbit interactions [21]… …introduce three cases of strongly correlated system: Mott insulator, Bose glass and Kondo… …of MI-BG transitions. 1.2.3 Kondo insulator The Kondo lattice is another type of…

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APA (6^th Edition):

Hong, S. (2013). Renormalization for insulating states of matter. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/44258

Chicago Manual of Style (16^th Edition):

Hong, Seungmin. “Renormalization for insulating states of matter.” 2013. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 26, 2021. http://hdl.handle.net/2142/44258.

MLA Handbook (7^th Edition):

Hong, Seungmin. “Renormalization for insulating states of matter.” 2013. Web. 26 Jan 2021.

Vancouver:

Hong S. Renormalization for insulating states of matter. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2013. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2142/44258.

Council of Science Editors:

Hong S. Renormalization for insulating states of matter. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2013. Available from: http://hdl.handle.net/2142/44258

7. He, Xiaoxiao. Surface Investigations of Novel Materials with Low Energy Ion Scattering.

Degree: Physics, 2012, University of California – Riverside

URL: http://www.escholarship.org/uc/item/4mg727p0

► Low energy ion scattering (LEIS) is an experimental technique that is of great utility in surface investigations of novel materials. LEIS is uniquely sensitive to… (more)

▼ Low energy ion scattering (LEIS) is an experimental technique that is of great utility in surface investigations of novel materials. LEIS is uniquely sensitive to the composition of the outermost atomic layer of a solid and can be used to determine the structure of the lattice in the near-surface region of a single crystal. More recently, it has been shown that the neutralization of scattered low energy alkali ions, which occurs via resonant charge transfer (RCT), is sensitive to the localized surface electronic structure. This thesis further demonstrates that RCT during LEIS reveals correlated-electron behavior at high temperature. The valence electron of a singly charged alkaline-earth ion is a magnetic impurity that interacts with the continuum of many-body excitations in the metal, leading to Kondo and mixed valence resonances near the Fermi energy. The occupation of these resonances is acutely sensitive to the surface temperature, which results in a marked temperature dependence of the ion neutralization. While the neutralization of magnesium (Mg) and gallium (Ga) scattered from polycrystalline gold (Au) shows little dependence on temperature, scattered strontium (Sr) does show an anomalous temperature dependence that provides clear evidence of electron correlations. The difference in neutralization between the alkaline earth Mg and Sr projectiles is discussed in terms of the velocity of the outgoing projectiles.The Topological Insulator, Bismuth Selenide (Bi₂Se₃), is comprised of Se-Bi-Se-Bi-Se quintuple layers (QLs), so that Se should terminate the stable surface. After cleaving in ultra-high vacuum at room temperature, however, low energy electron diffraction shows order while low energy Na⁺ LEIS reveals a Bi-termination. After cleaving at 80 K, the Se:Bi ratio measured by LEIS is enhanced, but slowly decreases to the room temperature value. Density functional theory suggests that a Bi bilayer positioned atop the nominal Se termination is energetically favorable and consistent with ARPES results from the literature. It is thus concluded that Bi₂Se₃ cleaves between the QLs, but that a thermally activated process leads to the Bi termination. This observation may resolve issues concerning the long-term stability of such materials.

Subjects/Keywords: Physics; Kondo effect; low energy ion scattering; novel materials; surface investigation; Topological insulator

…the density of filled states in the metal, and shows the position where a Kondo resonance… …correlations (Kondo resonance) are detected by low energy alkaline earth metal ion…

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APA (6^th Edition):

He, X. (2012). Surface Investigations of Novel Materials with Low Energy Ion Scattering. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/4mg727p0

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):

He, Xiaoxiao. “Surface Investigations of Novel Materials with Low Energy Ion Scattering.” 2012. Thesis, University of California – Riverside. Accessed January 26, 2021. http://www.escholarship.org/uc/item/4mg727p0.

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

MLA Handbook (7^th Edition):

He, Xiaoxiao. “Surface Investigations of Novel Materials with Low Energy Ion Scattering.” 2012. Web. 26 Jan 2021.

Vancouver:

He X. Surface Investigations of Novel Materials with Low Energy Ion Scattering. [Internet] [Thesis]. University of California – Riverside; 2012. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/4mg727p0.

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

Council of Science Editors:

He X. Surface Investigations of Novel Materials with Low Energy Ion Scattering. [Thesis]. University of California – Riverside; 2012. Available from: http://www.escholarship.org/uc/item/4mg727p0

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

University of Michigan

8. Cooley, Jason Christopher. High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride.

Degree: PhD, Pure Sciences, 1997, University of Michigan

URL: http://hdl.handle.net/2027.42/130630

► High pressure transport and magnetotransport measurements on the rare earth systems SmB₆, Ce_3Bi_4Pt₃ and EuB₆ as well as high pressure magnetic measurements on EuB₆ are… (more)

Subjects/Keywords: Cerium Bismuth Platinide; Earth; Europium Hexaboride; High; Kondo Insulator; Measurements; Pressure; Rare; Samarium Hexaboride; Systems; Transport

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APA (6^th Edition):

Cooley, J. C. (1997). High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/130630

Chicago Manual of Style (16^th Edition):

Cooley, Jason Christopher. “High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride.” 1997. Doctoral Dissertation, University of Michigan. Accessed January 26, 2021. http://hdl.handle.net/2027.42/130630.

MLA Handbook (7^th Edition):

Cooley, Jason Christopher. “High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride.” 1997. Web. 26 Jan 2021.

Vancouver:

Cooley JC. High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride. [Internet] [Doctoral dissertation]. University of Michigan; 1997. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2027.42/130630.

Council of Science Editors:

Cooley JC. High pressure transport measurements on the rare earth systems samarium hexaboride, cerium bismuth platinide and europium hexaboride. [Doctoral Dissertation]. University of Michigan; 1997. Available from: http://hdl.handle.net/2027.42/130630

9. Bazzanella, Matteo. Non-Linear Canonical Methods in Strongly Correlated Electron Systems.

Degree: 2014, University of Gothenburg / Göteborgs Universitet

URL: http://hdl.handle.net/2077/37148

► In this thesis some new ideas to perform the analysis of Strongly Correlated Electronic Systems (SCES) are developed. In particular the use of non-linear canonical… (more)

▼ In this thesis some new ideas to perform the analysis of Strongly Correlated Electronic Systems (SCES) are developed. In particular the use of non-linear canonical transformations is considered thoroughly. Using such transformations it is possible, in some circumstances, to simplify the quantum problem redefining the fermionic degrees of freedom used to describe the system. To understand and use effectively these non-linear transformations it is convenient to work in the Majorana fermion representation, i.e., to represent the quantum mechanical operators in terms of Majorana fermions. These objects can be imagined as algebraic constituents of the fermionic degrees of freedom. In a fermionic system, different equivalent sets of (emergent) Majorana fermions can be used to build the fermionic operators that characterize the system. The non-linear transformations can be seen as a way to mix these equivalent sets. Thanks to this insight, it becomes possible to determine the full structure of the group of canonical transformations and to identify an advantageous framework, which allows their use in the study of a generic SCES system. To test these statements the Hubbard and the Kondo lattice models were intensively studied making use of non-linear canonical transformations, obtaining interesting results in both cases. For example, in the Hubbard model a free fermion mean-field description of the paramagnetic Mott insulator was identified, while in the Kondo lattice it was possible to describe already at mean-field level the spin-selective Kondo insulating phase, consistently (from a quantitative and qualitative point of view) with the known numerical results. Moreover the method elaborated for the study of the Hubbard model is suitable for a systematic generalization to other situations and shows great room for improvement. These results prove that, thanks to the redefinition of the degrees of freedom used in the analysis of the system, it becomes possible to obtain quite non-trivial results already at mean-field level, or to consider very involved (but meaningful) correlated quantum states via simple variational trial states. This will potentially permit a more judicious and profitable choice of the fundamental degrees of freedom, allowing for an improvement of the efficiency of the analytical and numerical techniques used in the analysis of many SCES systems.

Subjects/Keywords: Majorana fermions; Emergent Majorana fermions; Non-linear transformation; canonical transformation; Kondo lattice; Mott insulator; Mean-field; Path-integral

…Application: the Hubbard model 4 The Mott Insulator 4.1 Metals and Insulators . . . . . . . . 4.2… …Mott physics . . . . . . . . . . . . . 4.2.1 A correlation driven insulator 4.2.2 Metal… …Insulator transition . . . . . . . . . . . . . . 39… …Achievements of Paper B . . . . . . . . . . . . . . . . . . . . . . 68 III Application: the Kondo… …lattice model 69 6 The Kondo lattice model 71 6.1 From real materials to the model…

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

APA (6^th Edition):

Bazzanella, M. (2014). Non-Linear Canonical Methods in Strongly Correlated Electron Systems. (Thesis). University of Gothenburg / Göteborgs Universitet. Retrieved from http://hdl.handle.net/2077/37148

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):

Bazzanella, Matteo. “Non-Linear Canonical Methods in Strongly Correlated Electron Systems.” 2014. Thesis, University of Gothenburg / Göteborgs Universitet. Accessed January 26, 2021. http://hdl.handle.net/2077/37148.

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

MLA Handbook (7^th Edition):

Bazzanella, Matteo. “Non-Linear Canonical Methods in Strongly Correlated Electron Systems.” 2014. Web. 26 Jan 2021.

Vancouver:

Bazzanella M. Non-Linear Canonical Methods in Strongly Correlated Electron Systems. [Internet] [Thesis]. University of Gothenburg / Göteborgs Universitet; 2014. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2077/37148.

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

Council of Science Editors:

Bazzanella M. Non-Linear Canonical Methods in Strongly Correlated Electron Systems. [Thesis]. University of Gothenburg / Göteborgs Universitet; 2014. Available from: http://hdl.handle.net/2077/37148

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

University of Queensland

10. Pillay, Jason Cornelius. Matrix product state study of strongly-interacting systems and quantum phase transitions.

Degree: School of Mathematics and Physics, 2020, University of Queensland

URL: https://espace.library.uq.edu.au/view/UQ:aadf24e/thumbnail_s4398997_final_thesis_t.jpg ; https://espace.library.uq.edu.au/view/UQ:aadf24e/s4398997_final_thesis.pdf ; https://espace.library.uq.edu.au/view/UQ:aadf24e

Subjects/Keywords: Matrix product states; Density-matrix renormalization group; Symmetry-protected topological order; Quantum phase transition; Entanglement spectrum; Topological Kondo insulator; Higher-order cumulants; Critical exponents; Scaling functions; Finite-entanglement scaling; 0204 Condensed Matter Physics; 0206 Quantum Physics

Record Details Similar Records Cite « Share

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

APA (6^th Edition):

Pillay, J. C. (2020). Matrix product state study of strongly-interacting systems and quantum phase transitions. (Thesis). University of Queensland. Retrieved from https://espace.library.uq.edu.au/view/UQ:aadf24e/thumbnail_s4398997_final_thesis_t.jpg ; https://espace.library.uq.edu.au/view/UQ:aadf24e/s4398997_final_thesis.pdf ; https://espace.library.uq.edu.au/view/UQ:aadf24e

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):

Pillay, Jason Cornelius. “Matrix product state study of strongly-interacting systems and quantum phase transitions.” 2020. Thesis, University of Queensland. Accessed January 26, 2021. https://espace.library.uq.edu.au/view/UQ:aadf24e/thumbnail_s4398997_final_thesis_t.jpg ; https://espace.library.uq.edu.au/view/UQ:aadf24e/s4398997_final_thesis.pdf ; https://espace.library.uq.edu.au/view/UQ:aadf24e.

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

MLA Handbook (7^th Edition):

Pillay, Jason Cornelius. “Matrix product state study of strongly-interacting systems and quantum phase transitions.” 2020. Web. 26 Jan 2021.

Vancouver:

Pillay JC. Matrix product state study of strongly-interacting systems and quantum phase transitions. [Internet] [Thesis]. University of Queensland; 2020. [cited 2021 Jan 26]. Available from: https://espace.library.uq.edu.au/view/UQ:aadf24e/thumbnail_s4398997_final_thesis_t.jpg ; https://espace.library.uq.edu.au/view/UQ:aadf24e/s4398997_final_thesis.pdf ; https://espace.library.uq.edu.au/view/UQ:aadf24e.

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

Council of Science Editors:

Pillay JC. Matrix product state study of strongly-interacting systems and quantum phase transitions. [Thesis]. University of Queensland; 2020. Available from: https://espace.library.uq.edu.au/view/UQ:aadf24e/thumbnail_s4398997_final_thesis_t.jpg ; https://espace.library.uq.edu.au/view/UQ:aadf24e/s4398997_final_thesis.pdf ; https://espace.library.uq.edu.au/view/UQ:aadf24e

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

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