subject:(BCS BEC Crossover)

University of Texas – Austin

1. Jiang, Minxi. Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover.

Degree: PhD, Physics, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2011-08-4288

► As the hydrodynamic theory breaks down with the local density ap- proximation in the fermionic superﬂuid with spin-polarization, we develop a general formalism of the… (more)

Subjects/Keywords: BEC-BCS crossover; Low-lying collective modes; Adiabatic dynamics

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APA (6^th Edition):

Jiang, M. (2011). Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2011-08-4288

Chicago Manual of Style (16^th Edition):

Jiang, Minxi. “Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover.” 2011. Doctoral Dissertation, University of Texas – Austin. Accessed January 19, 2021. http://hdl.handle.net/2152/ETD-UT-2011-08-4288.

MLA Handbook (7^th Edition):

Jiang, Minxi. “Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover.” 2011. Web. 19 Jan 2021.

Vancouver:

Jiang M. Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2011. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2152/ETD-UT-2011-08-4288.

Council of Science Editors:

Jiang M. Adiabatic dynamics of low-lying collective modes in the BEC-BCS crossover. [Doctoral Dissertation]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/ETD-UT-2011-08-4288

2. Lepers, Thomas. Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment.

Degree: Docteur es, Physique nucléaire et théorique, 2010, Université Claude Bernard – Lyon I

URL: http://www.theses.fr/2010LYO10113

►

Grace aux progrès énormes des techniques de refroidissement, des expériences actuelles avec des atomes fermioniques piégés atteignent des températures extrêmement basses de l'ordre du nanoKelvin.… (more)

▼

Grace aux progrès énormes des techniques de refroidissement, des expériences actuelles avec des atomes fermioniques piégés atteignent des températures extrêmement basses de l'ordre du nanoKelvin. Le but principal de ces expériences est l'étude de la transition nommée "BEC-BCS crossover". Pour cela, on change le champ magnétique autour d'une résonance de Feschbach, ce qui implique que la longueur de diffusion change des valeurs répulsives (a positif), à travers la limite unitaire (a infini) aux valeurs attractives (a négatif). Du côté BEC, où le système forme un condensat de Bose-Einstein de molécules fortement liées, aussi bien que du côté BCS, où les atomes forment des paires de Cooper qui ont une grande extension par rapport à la distance moyenne entre les atomes, on s'attend à ce que le système devienne superfluide, à condition que la température soit inférieure à une certaine température critique. Afin de trouver des signes sans équivoque de la superfluidité, il est nécessaire de regarder des observables dynamiques comme l'expansion du nuage atomique lorsque le piège est éteint ou des oscillations collectives du nuage. Le travail effectué au cours de cette thèse est une étude de la dynamique des modes collectifs dans les gaz de fermions froids. Nous avons développé un modèle basé sur l'évaluation de la matrice T. L'utilisation de l'équation de transport de Boltzmann pour les particules permet ensuite une étude semi-numérique des modes collectifs dans tous les régimes d'interaction. Cette étude a permis de mettre en évidence pour la première fois que la fréquence du mode radial quadrupolaire est supérieure à deux fois la fréquence du piège, comme cela est vérifié expérimentalement et contrairement aux premières théories n'incluant pas les effets de champ moyen. Les résultats obtenus ont aussi mis en évidence la nécessité d'une résolution numérique complète de l'équation de Boltzmann et de l'amélioration des techniques de détermination des observables physiques du gaz. Cette résolution numérique de l'équation de Boltzmann a montré que la détermination du temps de relaxation par la méthode des moments est erronée de 30%, ce qui influe fortement sur la détermination de la fréquence et de l'amortissement du mode collectif. Enfin, l'amélioration de la méthode des moments, considérant l'ordre supérieur, permet d'améliorer sensiblement l'accord avec le résultat numérique. Une telle investigation n'avait jamais été réalisée et montre la nécessité de considérer les moments d'ordre supérieurs pour l'étude des modes collectifs par l'équation de Boltzmann d'un gaz de fermions dans la phase normale

Due to the improvement of cooling technics, recent experiments on ultracold Fermi gases now reach temperatures in the range of the nanokelvin. The main goal of these experiments is to study the so called BEC-BCS crossover. By tuning the external magnetic field around a Feschbach resonance, the scattering lengh runs from the repulsive side (a>0) to the attractive side (a<0) through the unitarity limit (a infinite). In the BEC…

Advisors/Committee Members: Davesne, Dany (thesis director).

Subjects/Keywords: BEC BCS crossover; Equation Boltzmann; Mode collectif; Méthode des moments; Effets de milieu; BEC BCS crossover; Boltzmann equation; Collective mode; Methods of moments; 530

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

APA (6^th Edition):

Lepers, T. (2010). Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment. (Doctoral Dissertation). Université Claude Bernard – Lyon I. Retrieved from http://www.theses.fr/2010LYO10113

Chicago Manual of Style (16^th Edition):

Lepers, Thomas. “Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment.” 2010. Doctoral Dissertation, Université Claude Bernard – Lyon I. Accessed January 19, 2021. http://www.theses.fr/2010LYO10113.

MLA Handbook (7^th Edition):

Lepers, Thomas. “Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment.” 2010. Web. 19 Jan 2021.

Vancouver:

Lepers T. Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment. [Internet] [Doctoral dissertation]. Université Claude Bernard – Lyon I; 2010. [cited 2021 Jan 19]. Available from: http://www.theses.fr/2010LYO10113.

Council of Science Editors:

Lepers T. Étude dynamique des modes collectifs dans les gaz de fermions froids : Study of secondary charged particles emission to monitor in-line dosimetry during hadrontherapy treatment. [Doctoral Dissertation]. Université Claude Bernard – Lyon I; 2010. Available from: http://www.theses.fr/2010LYO10113

Universiteit Utrecht

3. Romans, Matheus Wilhelmus Jozef. Dressed molecules in atomic quantum gases.

Degree: 2007, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/19724

► The use of Feshbach resonances in the field of ultracold gases has received a lot of attention recently. In first instance it was realized that… (more)

▼ The use of Feshbach resonances in the field of ultracold gases has received a lot of attention recently. In first instance it was realized that these resonances can be used to alter the interaction strength in an atomic gas, by means of tuning an external magnetic field. Furthermore, by sweeping the magnetic field from one side of the resonance to the other, a degenerate gas of bosonic molecules can be created, a significant accomplishment. By making the interactions between fermionic atoms strongly attractive, a fermionic superfluid was recently made, a feat that has drawn a lot of attention in the physics community and from the media. We present work that describes these many-particle systems near a Feshbach resonance in a comprehensive way by using the concept of dressed molecules. These dressed molecules are essentially two-particle states that are a superposition of a tightly bound bare molecule, and two unbound bare atoms. This description reduces to the correct paired wave-function in the two-body limit. Moreover it gives a physically correct description of all the phenomena mentioned above: the Bose-condensation of a gas near a Feshbach resonance, that contains molecules, is more correctly interpreted as a Bose-condensation of dressed molecules. The fermionic superfluid contains a condensate of bosonic pairs, normally called Cooper pairs, that can be understood as the dressed molecules. For the latter case, the dressed-molecule picture also gives an elegant characterization of the crossover between a Bose condensate of pure molecules on one side of the resonance, to a fermionic Bardeen-Cooper-Schrieffer superfluid on the other side. Then, the dressed molecules change continuously from being mostly a bare molecule, to being mostly a loose pair of two atoms. It is clear that the nature of the dressed molecules is much determined by the probability for it to be in the bare-molecular state. This probability we denote with a single parameter Z. We present various ways of calculating it, and study how it affects the macroscopic physics.

Subjects/Keywords: Natuur- en Sterrenkunde; dressed molecule; ultracold; quantum; crossover; BEC; BCS; Feshbach resonance

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APA (6^th Edition):

Romans, M. W. J. (2007). Dressed molecules in atomic quantum gases. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/19724

Chicago Manual of Style (16^th Edition):

Romans, Matheus Wilhelmus Jozef. “Dressed molecules in atomic quantum gases.” 2007. Doctoral Dissertation, Universiteit Utrecht. Accessed January 19, 2021. http://dspace.library.uu.nl:8080/handle/1874/19724.

MLA Handbook (7^th Edition):

Romans, Matheus Wilhelmus Jozef. “Dressed molecules in atomic quantum gases.” 2007. Web. 19 Jan 2021.

Vancouver:

Romans MWJ. Dressed molecules in atomic quantum gases. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2007. [cited 2021 Jan 19]. Available from: http://dspace.library.uu.nl:8080/handle/1874/19724.

Council of Science Editors:

Romans MWJ. Dressed molecules in atomic quantum gases. [Doctoral Dissertation]. Universiteit Utrecht; 2007. Available from: http://dspace.library.uu.nl:8080/handle/1874/19724

Georgia Tech

4. Iskin, Menderes. BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases.

Degree: PhD, Physics, 2007, Georgia Tech

URL: http://hdl.handle.net/1853/16326

► This thesis focuses on the analysis of Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) evolution in ultracold superfluid Fermi gases when the interaction between atoms is… (more)

Subjects/Keywords: Fermi gas; Ultracold; Quantum phase transition; BEC; BCS; Crossover; BCS-BEC

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APA (6^th Edition):

Iskin, M. (2007). BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/16326

Chicago Manual of Style (16^th Edition):

Iskin, Menderes. “BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases.” 2007. Doctoral Dissertation, Georgia Tech. Accessed January 19, 2021. http://hdl.handle.net/1853/16326.

MLA Handbook (7^th Edition):

Iskin, Menderes. “BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases.” 2007. Web. 19 Jan 2021.

Vancouver:

Iskin M. BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases. [Internet] [Doctoral dissertation]. Georgia Tech; 2007. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1853/16326.

Council of Science Editors:

Iskin M. BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases. [Doctoral Dissertation]. Georgia Tech; 2007. Available from: http://hdl.handle.net/1853/16326

Uniwersytet im. Adama Mickiewicza w Poznaniu

5. Cichy, Agnieszka. Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów .

Degree: 2012, Uniwersytet im. Adama Mickiewicza w Poznaniu

URL: http://hdl.handle.net/10593/2813

► Głównym celem pracy doktorskiej było zbadanie wpływu pola magnetycznego Zeemana na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów. Ewolucja układu od… (more)

Subjects/Keywords: Nadprzewodnictwo; Superconductivity; Spinowo-spolaryzowany model Hubbarda i rozszerzenia; Extended spin-polarized Hubbard model; Przejście BCS-BEC; BCS-BEC crossover; Ultrazimne gazy fermionowe na sieci; Ultracold atomic Fermi gases on lattice

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

APA (6^th Edition):

Cichy, A. (2012). Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów . (Doctoral Dissertation). Uniwersytet im. Adama Mickiewicza w Poznaniu. Retrieved from http://hdl.handle.net/10593/2813

Chicago Manual of Style (16^th Edition):

Cichy, Agnieszka. “Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów .” 2012. Doctoral Dissertation, Uniwersytet im. Adama Mickiewicza w Poznaniu. Accessed January 19, 2021. http://hdl.handle.net/10593/2813.

MLA Handbook (7^th Edition):

Cichy, Agnieszka. “Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów .” 2012. Web. 19 Jan 2021.

Vancouver:

Cichy A. Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów . [Internet] [Doctoral dissertation]. Uniwersytet im. Adama Mickiewicza w Poznaniu; 2012. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/10593/2813.

Council of Science Editors:

Cichy A. Wpływ pola magnetycznego na własności nadprzewodzące i przejście BCS-BEC w układach z lokalnym parowaniem fermionów . [Doctoral Dissertation]. Uniwersytet im. Adama Mickiewicza w Poznaniu; 2012. Available from: http://hdl.handle.net/10593/2813

University of Colorado

6. Shen, Zhaochuan. The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids.

Degree: PhD, Physics, 2014, University of Colorado

URL: https://scholar.colorado.edu/phys_gradetds/123

► This dissertation presents the theoretical study of two-component fermionic gases. It firstly studies the BCS-BEC crossover for the system of the two-component fermionic gas… (more)

Subjects/Keywords: BCS-BEC Crossover; Bethe Ansatz; Feshbach Resonance; Optical Lattices; Quantum Quench; Atomic, Molecular and Optical Physics; Physics

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

APA (6^th Edition):

Shen, Z. (2014). The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/123

Chicago Manual of Style (16^th Edition):

Shen, Zhaochuan. “The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids.” 2014. Doctoral Dissertation, University of Colorado. Accessed January 19, 2021. https://scholar.colorado.edu/phys_gradetds/123.

MLA Handbook (7^th Edition):

Shen, Zhaochuan. “The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids.” 2014. Web. 19 Jan 2021.

Vancouver:

Shen Z. The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2021 Jan 19]. Available from: https://scholar.colorado.edu/phys_gradetds/123.

Council of Science Editors:

Shen Z. The Study of the BCS-BEC Crossover in Optical Lattices and of Quenches in Paired Superfluids. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/phys_gradetds/123

Rice University

7. Jiang, Lei. Probing and Manipulating Ultracold Fermi Superfluids.

Degree: PhD, Natural Sciences, 2012, Rice University

URL: http://hdl.handle.net/1911/70279

► Ultracold Fermi gas is an exciting field benefiting from atomic physics, optical physics and condensed matter physics. It covers many aspects of quantum mechanics. Here… (more)

▼ Ultracold Fermi gas is an exciting field benefiting from atomic physics, optical physics and condensed matter physics. It covers many aspects of quantum mechanics. Here I introduce some of my work during my graduate study. We proposed an optical spectroscopic method based on electromagnetically-induced transparency (EIT) as a generic probing tool that provides valuable insights into the nature of Fermi paring in ultracold Fermi gases of two hyperfine states. This technique has the capability of allowing spectroscopic response to be determined in a nearly non-destructive manner and the whole spectrum may be obtained by scanning the probe laser frequency faster than the lifetime of the sample without re-preparing the atomic sample repeatedly. Both quasiparticle picture and pseudogap picture are constructed to facilitate the physical explanation of the pairing signature in the EIT spectra. Motivated by the prospect of realizing a Fermi gas of 40 K atoms with a synthetic non-Abelian gauge field, we investigated theoretically BEC-HCS crossover physics in the presence of a Rashba spin-orbit coupling in a system of two-component Fermi gas with and without a Zeeman field that breaks the population balance. A new bound state (Rashba pair) emerges because of the spin-orbit interaction. We studied the properties of Rashba pairs using a standard pair fluctuation theory. As the two-fold spin degeneracy is lifted by spin-orbit interaction, bound pairs with mixed singlet and triplet pairings (referred to as rashbons) emerge, leading to an anisotropic superfluid. We discussed in detail the experimental signatures for observing the condensation of Rashba pairs by calculating various physical observables which characterize the properties of the system and can be measured in experiment. The role of impurities as experimental probes in the detection of quantum material properties is well appreciated. Here we studied the effect of a single classical impurity in trapped ultracold Fermi superfluids. Although a non-magnetic impurity does not change macroscopic properties of s-wave Fermi superfluids, depending on its shape and strength, a magnetic impurity can induce single or multiple mid-gap bound states. The multiple mid-gap states could coincide with the development of a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase within the superfluid. As an analog of the Scanning Tunneling Microscope, we proposed a modified radio frequency spectroscopic method to measure the focal density of states which can be employed to detect these states and other quantum phases of cold atoms. A key result of our self consistent Bogoliubov-de Gennes calculations is that a magnetic impurity can controllably induce an FFLO state at currently accessible experimental parameters. Advisors/Committee Members: Pu, Han (advisor).

Subjects/Keywords: Pure sciences; Ultracold gased; Degenerate Fermi gases; Superfluids; BEC-BCS crossover; Low temperature physics; Condensed matter physics; Atoms; Subatomic particles

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

APA (6^th Edition):

Jiang, L. (2012). Probing and Manipulating Ultracold Fermi Superfluids. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/70279

Chicago Manual of Style (16^th Edition):

Jiang, Lei. “Probing and Manipulating Ultracold Fermi Superfluids.” 2012. Doctoral Dissertation, Rice University. Accessed January 19, 2021. http://hdl.handle.net/1911/70279.

MLA Handbook (7^th Edition):

Jiang, Lei. “Probing and Manipulating Ultracold Fermi Superfluids.” 2012. Web. 19 Jan 2021.

Vancouver:

Jiang L. Probing and Manipulating Ultracold Fermi Superfluids. [Internet] [Doctoral dissertation]. Rice University; 2012. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1911/70279.

Council of Science Editors:

Jiang L. Probing and Manipulating Ultracold Fermi Superfluids. [Doctoral Dissertation]. Rice University; 2012. Available from: http://hdl.handle.net/1911/70279

Kyoto University

8. Adachi, Kyosuke. Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime .

Degree: 2019, Kyoto University

URL: http://hdl.handle.net/2433/242584

Subjects/Keywords: superconductivity; BCS-BEC crossover; superconducting fluctuation; vortex liquid; dimensionality

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

APA (6^th Edition):

Adachi, K. (2019). Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/242584

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):

Adachi, Kyosuke. “Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime .” 2019. Thesis, Kyoto University. Accessed January 19, 2021. http://hdl.handle.net/2433/242584.

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

MLA Handbook (7^th Edition):

Adachi, Kyosuke. “Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime .” 2019. Web. 19 Jan 2021.

Vancouver:

Adachi K. Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime . [Internet] [Thesis]. Kyoto University; 2019. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2433/242584.

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

Council of Science Editors:

Adachi K. Fluctuation and dimensionality effects on superconductivity in the BCS-BEC crossover regime . [Thesis]. Kyoto University; 2019. Available from: http://hdl.handle.net/2433/242584

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

9. Romans, Matheus Wilhelmus Jozef. Dressed molecules in atomic quantum gases.

Degree: 2007, University Utrecht

URL: https://dspace.library.uu.nl/handle/1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; 1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; https://dspace.library.uu.nl/handle/1874/19724

► The use of Feshbach resonances in the field of ultracold gases has received a lot of attention recently. In first instance it was realized that… (more)

▼ The use of Feshbach resonances in the field of ultracold gases has received a lot of attention recently. In first instance it was realized that these resonances can be used to alter the interaction strength in an atomic gas, by means of tuning an external magnetic field. Furthermore, by sweeping the magnetic field from one side of the resonance to the other, a degenerate gas of bosonic molecules can be created, a significant accomplishment. By making the interactions between fermionic atoms strongly attractive, a fermionic superfluid was recently made, a feat that has drawn a lot of attention in the physics community and from the media. We present work that describes these many-particle systems near a Feshbach resonance in a comprehensive way by using the concept of dressed molecules. These dressed molecules are essentially two-particle states that are a superposition of a tightly bound bare molecule, and two unbound bare atoms. This description reduces to the correct paired wave-function in the two-body limit. Moreover it gives a physically correct description of all the phenomena mentioned above: the Bose-condensation of a gas near a Feshbach resonance, that contains molecules, is more correctly interpreted as a Bose-condensation of dressed molecules. The fermionic superfluid contains a condensate of bosonic pairs, normally called Cooper pairs, that can be understood as the dressed molecules. For the latter case, the dressed-molecule picture also gives an elegant characterization of the crossover between a Bose condensate of pure molecules on one side of the resonance, to a fermionic Bardeen-Cooper-Schrieffer superfluid on the other side. Then, the dressed molecules change continuously from being mostly a bare molecule, to being mostly a loose pair of two atoms. It is clear that the nature of the dressed molecules is much determined by the probability for it to be in the bare-molecular state. This probability we denote with a single parameter Z. We present various ways of calculating it, and study how it affects the macroscopic physics.

Subjects/Keywords: dressed molecule; ultracold; quantum; crossover; BEC; BCS; Feshbach resonance

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

APA (6^th Edition):

Romans, M. W. J. (2007). Dressed molecules in atomic quantum gases. (Doctoral Dissertation). University Utrecht. Retrieved from https://dspace.library.uu.nl/handle/1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; 1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; https://dspace.library.uu.nl/handle/1874/19724

Chicago Manual of Style (16^th Edition):

Romans, Matheus Wilhelmus Jozef. “Dressed molecules in atomic quantum gases.” 2007. Doctoral Dissertation, University Utrecht. Accessed January 19, 2021. https://dspace.library.uu.nl/handle/1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; 1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; https://dspace.library.uu.nl/handle/1874/19724.

MLA Handbook (7^th Edition):

Romans, Matheus Wilhelmus Jozef. “Dressed molecules in atomic quantum gases.” 2007. Web. 19 Jan 2021.

Vancouver:

Romans MWJ. Dressed molecules in atomic quantum gases. [Internet] [Doctoral dissertation]. University Utrecht; 2007. [cited 2021 Jan 19]. Available from: https://dspace.library.uu.nl/handle/1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; 1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; https://dspace.library.uu.nl/handle/1874/19724.

Council of Science Editors:

Romans MWJ. Dressed molecules in atomic quantum gases. [Doctoral Dissertation]. University Utrecht; 2007. Available from: https://dspace.library.uu.nl/handle/1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; 1874/19724 ; URN:NBN:NL:UI:10-1874-19724 ; https://dspace.library.uu.nl/handle/1874/19724

University of Michigan

10. Yi, Wei. BCS-BEC crossover in an ultracold Fermi gas.

Degree: PhD, Pure Sciences, 2007, University of Michigan

URL: http://hdl.handle.net/2027.42/126598

► This thesis summarizes our study on the properties of ultracold Fermions near a Feshbach resonance. The Feshbach resonance allows for a continuous tuning of the… (more)

▼ This thesis summarizes our study on the properties of ultracold Fermions near a Feshbach resonance. The Feshbach resonance allows for a continuous tuning of the interaction strength between the atoms. With this tunability, many properties predicted for the BCS-BEC crossover region in solids can be shown to exist in this ultracold Fermi gas. With the highly controllable parameters and the clean environment in the experiments, the study of the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein Condensation (BEC) crossover in ultracold Fermions provides valuable insights to the strongly interacting crossover region, which has never been achieved before in solids. We first examine the properties of ⁶Li and ⁴⁰K gases. We find that in the unitary region the properties of the system do not depend on the atom species: outside the unitary region, the properties of the system do depend on the scattering properties of the different atom species. We study the dynamics of the ultracold Fermions in the crossover region in response to the variations in the external magnetic field. We find that the response depends on the time scale and the amplitude of the variations; which is in qualitative agreement with the experimental observations. We derive a set of dynamic mean-field equations for a Fermi gas in an arbitrary potential trap near a wide Feshbach resonance. The equations are more general than the local density approximation (LDA), and less demanding computationally as the Bogoliubov-de-Gennes (BdG) equation. We then analyze the solubility of the equations, as well as solve a simplified version of the equations for illustration and for self-consistency check on the assumptions made during the derivation. We systematically study the possible phases for a trapped Fermi gas with population imbalance near a Feshbach resonance. Our results agree qualitatively well with the recent experimental results, and predict the existence of two exotic non-BCS superfluid phases for the strongly interacting gas with population unbalance: the Breached Pair (BP) phase and the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. Finally, to guide the experimental efforts in the search of new quantum phases, we propose a detection scheme for the possible exotic phases. Advisors/Committee Members: Duan, Luming (advisor).

Subjects/Keywords: Bcs; Bec; Bose-einstein Condensate; Bose-einstein Condensates; Crossover; Fermi Gas; Superfluidity; Ultracold

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APA (6^th Edition):

Yi, W. (2007). BCS-BEC crossover in an ultracold Fermi gas. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/126598

Chicago Manual of Style (16^th Edition):

Yi, Wei. “BCS-BEC crossover in an ultracold Fermi gas.” 2007. Doctoral Dissertation, University of Michigan. Accessed January 19, 2021. http://hdl.handle.net/2027.42/126598.

MLA Handbook (7^th Edition):

Yi, Wei. “BCS-BEC crossover in an ultracold Fermi gas.” 2007. Web. 19 Jan 2021.

Vancouver:

Yi W. BCS-BEC crossover in an ultracold Fermi gas. [Internet] [Doctoral dissertation]. University of Michigan; 2007. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2027.42/126598.

Council of Science Editors:

Yi W. BCS-BEC crossover in an ultracold Fermi gas. [Doctoral Dissertation]. University of Michigan; 2007. Available from: http://hdl.handle.net/2027.42/126598

University of Washington

11. Richie-Halford, Adam. Quantum Monte Carlo Studies of the BCS-BEC crossover.

Degree: PhD, 2020, University of Washington

URL: http://hdl.handle.net/1773/46157

► This dissertation focuses on the physics of dilute Fermi gases in the so-called BCS-BEC crossover, with short-range attractive interactions and large scattering lengths. It introduces… (more)

Subjects/Keywords: BCS-BEC crossover; Neutron Matter; Pseudogap; Quantum Monte Carlo; Superfluidity; Unitary Fermi Gas; Physics; Condensed matter physics; Nuclear physics and radiation; Physics

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APA (6^th Edition):

Richie-Halford, A. (2020). Quantum Monte Carlo Studies of the BCS-BEC crossover. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/46157

Chicago Manual of Style (16^th Edition):

Richie-Halford, Adam. “Quantum Monte Carlo Studies of the BCS-BEC crossover.” 2020. Doctoral Dissertation, University of Washington. Accessed January 19, 2021. http://hdl.handle.net/1773/46157.

MLA Handbook (7^th Edition):

Richie-Halford, Adam. “Quantum Monte Carlo Studies of the BCS-BEC crossover.” 2020. Web. 19 Jan 2021.

Vancouver:

Richie-Halford A. Quantum Monte Carlo Studies of the BCS-BEC crossover. [Internet] [Doctoral dissertation]. University of Washington; 2020. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1773/46157.

Council of Science Editors:

Richie-Halford A. Quantum Monte Carlo Studies of the BCS-BEC crossover. [Doctoral Dissertation]. University of Washington; 2020. Available from: http://hdl.handle.net/1773/46157

University of Oslo

12. Lysebo, Marius. Photoassociation of ultracold atoms.

Degree: 2006, University of Oslo

URL: http://urn.nb.no/URN:NBN:no-12793 ; https://www.duo.uio.no/handle/10852/11136 ; Fulltext https://www.duo.uio.no/bitstream/handle/10852/11136/1/master.pdf

► Oppgaven ser på muligheten for å buke fotoassosiasjon som metode for å produsere kalde molekyler. Det gjøres eksplisitte regninger for Litium molekylet, og undersøkes i… (more)

Subjects/Keywords: fotoassosiasjon Li2 molekyl kalde atomer molekyler Feshbach resonanser BEC-BCS crossover; VDP::430

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APA (6^th Edition):

Lysebo, M. (2006). Photoassociation of ultracold atoms. (Thesis). University of Oslo. Retrieved from http://urn.nb.no/URN:NBN:no-12793 ; https://www.duo.uio.no/handle/10852/11136 ; Fulltext https://www.duo.uio.no/bitstream/handle/10852/11136/1/master.pdf

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):

Lysebo, Marius. “Photoassociation of ultracold atoms.” 2006. Thesis, University of Oslo. Accessed January 19, 2021. http://urn.nb.no/URN:NBN:no-12793 ; https://www.duo.uio.no/handle/10852/11136 ; Fulltext https://www.duo.uio.no/bitstream/handle/10852/11136/1/master.pdf.

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

MLA Handbook (7^th Edition):

Lysebo, Marius. “Photoassociation of ultracold atoms.” 2006. Web. 19 Jan 2021.

Vancouver:

Lysebo M. Photoassociation of ultracold atoms. [Internet] [Thesis]. University of Oslo; 2006. [cited 2021 Jan 19]. Available from: http://urn.nb.no/URN:NBN:no-12793 ; https://www.duo.uio.no/handle/10852/11136 ; Fulltext https://www.duo.uio.no/bitstream/handle/10852/11136/1/master.pdf.

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

Council of Science Editors:

Lysebo M. Photoassociation of ultracold atoms. [Thesis]. University of Oslo; 2006. Available from: http://urn.nb.no/URN:NBN:no-12793 ; https://www.duo.uio.no/handle/10852/11136 ; Fulltext https://www.duo.uio.no/bitstream/handle/10852/11136/1/master.pdf

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

Kyoto University

13. Shi, Anlu. Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe .

Degree: 2018, Kyoto University

URL: http://hdl.handle.net/2433/232460

Subjects/Keywords: Iron-based Superconductor; Nuclear Magnetic Resonance; BCS-BEC Crossover; Pseudogap Behavior; Superconducting Fluctuations

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APA (6^th Edition):

Shi, A. (2018). Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/232460

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):

Shi, Anlu. “Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe .” 2018. Thesis, Kyoto University. Accessed January 19, 2021. http://hdl.handle.net/2433/232460.

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

MLA Handbook (7^th Edition):

Shi, Anlu. “Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe .” 2018. Web. 19 Jan 2021.

Vancouver:

Shi A. Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe . [Internet] [Thesis]. Kyoto University; 2018. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2433/232460.

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

Council of Science Editors:

Shi A. Nuclear Magnetic Resonance Studies on Iron Chalcogenide FeSe . [Thesis]. Kyoto University; 2018. Available from: http://hdl.handle.net/2433/232460

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

Kent State University

14. Liao, Renyuan. Fermion Pairing and BEC-BCS Crossover in Novel Systems.

Degree: PhD, College of Arts and Sciences / Department of Physics, 2008, Kent State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883

► This dissertation covers my theoretical work in the field of pairing of fermions and BCS-BEC crossover behavior in various condensed matter systems. High temperature… (more)

▼ This dissertation covers my theoretical work in the field of pairing of fermions and BCS-BEC crossover behavior in various condensed matter systems. High temperature superconductors, heavy fermion systems, 2D semiconductors undergoing a semiconductor-superconductor transition, and ultracold atomic Fermi gases are examples of novel systems that provide us with a rich playground to study pairing phenomena such as superconductivity or superfluidity. In this dissertation, with ultracold fermions in mind, I attempt to address some of the outstanding theoretical issues regarding pairing of fermions for arbitrary interactions, and for arbitrary population and mass imbalance. In so doing, I explore pairing in Bose-Einstein condensation (BEC) and Bardeen-Cooper-Schrieffer (BCS) regimes, and the behavior at the BEC-BCS crossover. I investigate the stability of paired many-fermion ground states, e.g., superfluidity and phase separated states; and possible phase transitions between these ground states. The specific projects that I undertake at the mean-field level are: interplay of intra- and inter- species pairing correlations in determining s-wave pairing in spin-population imbalanced Fermi systems; p-wave pairing in systems with mismatched fermi surfaces; stability of “breached pairs” states with p-wave symmetry in BEC and BCS regimes; use of Bogoliubov-de Gennes equations to study spatial variation of the pairing order parameter; and superconductivity with unconventional pairing symmetries in 2D systems with an “inherent” gaps, such as in semiconducting systems. In the case of s-wave pairing in a spin-population imbalanced system, while the system phase separates into normal and superfluid components, I show that the inclusion of intra-species correlation stabilizes a supefluid phase, up to a critical polarization, on the BCS side. For S=1, m_s=0 triplet p-wave pairing in a population imbalanced system, I obtain a rich phase diagram. In addition to the states Δ_±1 propto Y_1±1, a multitude of “mixed” SF states formed of linear combinations of Y_1m's give global energy minimum under a phase stability condition. States with local minimum are also obtained. With increased polarization, the global minimum SF states may undergo a quantum phase transition to the local minimum SF states. I also study effects of finite temperature (T) and of mass imbalance (r) between the species. Though the features of the phase diagram are not changed qualitatively from the equal mass (r=1) case, the critical temperature T_c shows some interesting behavior for large polarization. Our p-wave pairing provides an arena to study “breached pairing” (BP), i.e., phase separation in momentum space. While this is not stable in BCS regime for s-wave pairing, I find that p-wave BP phases may be stable in both BCS and BEC regimes for arbitrary mass ratio, r. To explore many-body effects beyond mean-field, I study the effects of… Advisors/Committee Members: Quader, Khandker (Advisor).

Subjects/Keywords: Physics; Fermion pairing; BEC-BCS crossover; cold atom; imbalanced population

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APA (6^th Edition):

Liao, R. (2008). Fermion Pairing and BEC-BCS Crossover in Novel Systems. (Doctoral Dissertation). Kent State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883

Chicago Manual of Style (16^th Edition):

Liao, Renyuan. “Fermion Pairing and BEC-BCS Crossover in Novel Systems.” 2008. Doctoral Dissertation, Kent State University. Accessed January 19, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883.

MLA Handbook (7^th Edition):

Liao, Renyuan. “Fermion Pairing and BEC-BCS Crossover in Novel Systems.” 2008. Web. 19 Jan 2021.

Vancouver:

Liao R. Fermion Pairing and BEC-BCS Crossover in Novel Systems. [Internet] [Doctoral dissertation]. Kent State University; 2008. [cited 2021 Jan 19]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883.

Council of Science Editors:

Liao R. Fermion Pairing and BEC-BCS Crossover in Novel Systems. [Doctoral Dissertation]. Kent State University; 2008. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883

15. Watashige, Tatsuya. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements .

Degree: 2017, Kyoto University

URL: http://hdl.handle.net/2433/225391

Subjects/Keywords: Iron-based superconductor; BCS-BEC crossover; Thermal transport measurements; Highly spin imbalanced superconducting phase

1 more image…

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APA (6^th Edition):

Watashige, T. (2017). Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/225391

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):

Watashige, Tatsuya. “Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements .” 2017. Thesis, Kyoto University. Accessed January 19, 2021. http://hdl.handle.net/2433/225391.

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

MLA Handbook (7^th Edition):

Watashige, Tatsuya. “Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements .” 2017. Web. 19 Jan 2021.

Vancouver:

Watashige T. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements . [Internet] [Thesis]. Kyoto University; 2017. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2433/225391.

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

Council of Science Editors:

Watashige T. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements . [Thesis]. Kyoto University; 2017. Available from: http://hdl.handle.net/2433/225391

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

16. Watashige, Tatsuya. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定.

Degree: 博士(理学), 2017, Kyoto University / 京都大学

URL: http://hdl.handle.net/2433/225391 ; http://dx.doi.org/10.14989/doctor.k20166

新制・課程博士

甲第20166号

理博第4251号

Subjects/Keywords: Iron-based superconductor; BCS-BEC crossover; Thermal transport measurements; Highly spin imbalanced superconducting phase

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APA (6^th Edition):

Watashige, T. (2017). Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定. (Thesis). Kyoto University / 京都大学. Retrieved from http://hdl.handle.net/2433/225391 ; http://dx.doi.org/10.14989/doctor.k20166

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):

Watashige, Tatsuya. “Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定.” 2017. Thesis, Kyoto University / 京都大学. Accessed January 19, 2021. http://hdl.handle.net/2433/225391 ; http://dx.doi.org/10.14989/doctor.k20166.

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

MLA Handbook (7^th Edition):

Watashige, Tatsuya. “Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定.” 2017. Web. 19 Jan 2021.

Vancouver:

Watashige T. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定. [Internet] [Thesis]. Kyoto University / 京都大学; 2017. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2433/225391 ; http://dx.doi.org/10.14989/doctor.k20166.

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

Council of Science Editors:

Watashige T. Quasiparticle excitations in FeSe in the vicinity of BCS-BEC crossover studied by thermal transport measurements : FeSe単結晶における熱輸送係数の測定. [Thesis]. Kyoto University / 京都大学; 2017. Available from: http://hdl.handle.net/2433/225391 ; http://dx.doi.org/10.14989/doctor.k20166

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

17. Liu, Xiaomeng. Correlated Electron States in Coupled Graphene Double-Layer Heterostructures.

Degree: PhD, 2019, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121289

► Graphene have grown to be a major experimental platform for studying two-dimensional (2D) physics due to its high quality, versatility and tunablity. Created by stacking… (more)

▼ Graphene have grown to be a major experimental platform for studying two-dimensional (2D) physics due to its high quality, versatility and tunablity. Created by stacking graphene with other 2D materials, 2D heterostructures expand the possibility for exciting physics beyond graphene itself. This dissertation reports new phenomena observed in graphene double-layer heterostructures. In our devices, two graphene layers are placed in close proximity but separated by a thin hexagonal Boron Nitride (hBN) insulator, such that the two layers interact through Coulomb interaction while direct tunneling is prohibited. We used Coulomb drag effect to characterize the interactions between layers as well as probe interlayer correlated phases. Experimental effort in graphene double-layer device fabrication and Coulomb drag measurements are presented. In the high temperature and weak coupling regime, we studied frictional drag effect due to interlayer Coulomb scattering. By correlating the drag signal with transport behavior of each individual layer, we furthered our understanding of magneto- and Hall-drag effect in the quantum Hall regime. The most exciting possibility enabled by a double-layer electronic system is the exciton condensation (EC). Through Coulomb attraction, electrons in one layer and holes in the other layer bind into interlayer excitons, which are capable of establishing Bose-Einstein condensate under low temperatures. Graphene double-layer heterostructure, being highly tunable and strongly interacting, is a perfect system to realize this exotic superfluid state. EC of quasi-electrons and quasi-holes is first achieved between two partially filled Landau levels (LLs) in the same band in bilayer graphene double-layers. By studying the EC phase transition induced by perpendicular electric field, the conditions for LLs to establish EC is acquired. In monolayer graphene double-layers, a novel EC phase can be established between an electron-doped graphene and a hole-doped graphene with equal carrier densities. We call this state exciton insulator, as each layer is found to be insulating when the other layer is open-circuit. However, they become conducting if current is allowed to flow in the drag layer. A perfect drag current arises at the same time. This exciton insulator phase is similar to EC under zero magnetic field. Superfluids caused by condensation of fermion pairs, such as the exciton condensate, have two distinct types: Bose-Einstein condensation (BEC) and Bardeen–Cooper–Schrieffer (BCS) condensation. Tuning interlayer coupling strength, we observed BEC-BCS crossover of the exciton condensate. In the BEC limit, tightly bound excitons pairs first form exciton gas and subsequently condense at a much lower temperatures. Oppositely, when the coupling is weak (BCS), excitons, similar to Cooper pairs in a BCS superconductor, pair and condense simultaneously. This observation provides useful insight in studying other superfluids, such as high-Tc superconductors. With improved sample quality, more intricate interlayer… Advisors/Committee Members: Kim, Philip (advisor), Halperin, Bertrand I. (committee member), Yacoby, Amir (committee member).

Subjects/Keywords: Graphene; Exciton condensation; Coulomb Drag, Quantum Hall, Superfluid, BEC-BCS crossover, Fractional quantum Hall, Exciton Insulator

…and BEC-BCS crossover, which will be covered in Chapter 5. Interlayer exciton under zero… …electrons in the other layer through the Coulomb interaction, similar to phonon mediated BCS… …form a Bose-Einstein condensate (BEC), enabling macroscopic phase coherence and… …order to achieve condensation, a large density of excitons are needed as the BEC transition… …realize a exciton BEC without optical excitation (Fig. 1.3). Interlayer excitons…

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APA (6^th Edition):

Liu, X. (2019). Correlated Electron States in Coupled Graphene Double-Layer Heterostructures. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121289

Chicago Manual of Style (16^th Edition):

Liu, Xiaomeng. “Correlated Electron States in Coupled Graphene Double-Layer Heterostructures.” 2019. Doctoral Dissertation, Harvard University. Accessed January 19, 2021. http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121289.

MLA Handbook (7^th Edition):

Liu, Xiaomeng. “Correlated Electron States in Coupled Graphene Double-Layer Heterostructures.” 2019. Web. 19 Jan 2021.

Vancouver:

Liu X. Correlated Electron States in Coupled Graphene Double-Layer Heterostructures. [Internet] [Doctoral dissertation]. Harvard University; 2019. [cited 2021 Jan 19]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121289.

Council of Science Editors:

Liu X. Correlated Electron States in Coupled Graphene Double-Layer Heterostructures. [Doctoral Dissertation]. Harvard University; 2019. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121289

18. Sun, Deqiang. Landau-Zener transitions in noisy environment and many-body systems.

Degree: PhD, Physics, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773

► This dissertation discusses the Landau-Zener (LZ) theory and its application in noisy environments and in many-body systems. The first project considers the effect of fast… (more)

▼ This dissertation discusses the Landau-Zener (LZ) theory and its application in noisy environments and in many-body systems. The first project considers the effect of fast quantum noise on LZ transitions. There are two important time intervals separated by the characteristic LZ time. For each interval we derive and solve the evolution equation, and match the solutions at the boundaries to get a complete solution. Outside the LZ time interval, we derive the master equation, which differs from the classical equation by a quantum commutation term. Inside the LZ time interval, the mixed longitudinal-transverse noise correlation renormalizes the LZ gap and the system evolves according to the renormalized LZ gap. In the extreme quantum regime at zero temperature our theory gives a beautiful result which coincides with that of other authors. Our initial attempts to solve two experimental puzzles - an isotope effect and the quantized hysteresis curve of a single molecular magnet - are also discussed. The second project considers an ultracold dilute Fermi gas in a magnetic field sweeping across the broad Feshbach resonance. The broad resonance condition allows us to use the single mode approximation and to neglect the energy dispersion of the fermions. We then propose the Global Spin Model Hamiltonian, whose ground state we solve exactly, which yields the static limit properties of the BEC-BCS crossover. We also study the dynamics of the Global Spin Model by converting it to a LZ problem. The resulting molecular production from the initial fermions is described by a LZ-like formula with a strongly renormalized LZ gap that is independent of the initial fermion density. We predict that molecular production during a field-sweep strongly depends on the initial value of magnetic field. We predict that in the inverse process of molecular dissociation, immediately after the sweeping stops there appear Cooper pairs with parallel electronic spins and opposite momenta. Advisors/Committee Members: Pokrovsky, Valery L. (advisor), Abanov, Artem (committee member), Saslow, Wayne M. (committee member), Fulling, Stephen (committee member).

Subjects/Keywords: Landau-Zener theory; Fast quantum noise; Single molecular magnet; Mesoscopic Systems; Ultracold Fermi gas; BEC-BCS crossover

…is the single molecular magnet, and the second one is BCS-BEC crossover. In Chapter II we… …solve the static problem, which represents the static limit of the BEC-BCS crossover. For the… …BEC crossover. Chapter II discusses the LZ theory in the noisy environment. The review and… …will discuss the part related to molecular magnets and in Chapter III we will discuss the BCS…

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APA (6^th Edition):

Sun, D. (2010). Landau-Zener transitions in noisy environment and many-body systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773

Chicago Manual of Style (16^th Edition):

Sun, Deqiang. “Landau-Zener transitions in noisy environment and many-body systems.” 2010. Doctoral Dissertation, Texas A&M University. Accessed January 19, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773.

MLA Handbook (7^th Edition):

Sun, Deqiang. “Landau-Zener transitions in noisy environment and many-body systems.” 2010. Web. 19 Jan 2021.

Vancouver:

Sun D. Landau-Zener transitions in noisy environment and many-body systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773.

Council of Science Editors:

Sun D. Landau-Zener transitions in noisy environment and many-body systems. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-773

University of Manchester

19. Snape, Christopher. Applications of the Coupled Cluster Method to Pairing Problems.

Degree: 2010, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:78351

► The phenomenon of pairing in atomic and nuclear many-body systems gives rise to a great number of different physical properties of matter, from areas as… (more)

Subjects/Keywords: Normal Extended Coupled Cluster Method; Quartic Anharmonic Oscillator; Double Well Anharmonic Oscillator; SU(2) quasi spin pairing; BCS theory; BCS BEC Crossover; Ultracold Fermi Atom Gas; CCM; NCCM; ECCM

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APA (6^th Edition):

Snape, C. (2010). Applications of the Coupled Cluster Method to Pairing Problems. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:78351

Chicago Manual of Style (16^th Edition):

Snape, Christopher. “Applications of the Coupled Cluster Method to Pairing Problems.” 2010. Doctoral Dissertation, University of Manchester. Accessed January 19, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:78351.

MLA Handbook (7^th Edition):

Snape, Christopher. “Applications of the Coupled Cluster Method to Pairing Problems.” 2010. Web. 19 Jan 2021.

Vancouver:

Snape C. Applications of the Coupled Cluster Method to Pairing Problems. [Internet] [Doctoral dissertation]. University of Manchester; 2010. [cited 2021 Jan 19]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:78351.

Council of Science Editors:

Snape C. Applications of the Coupled Cluster Method to Pairing Problems. [Doctoral Dissertation]. University of Manchester; 2010. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:78351

University of Manchester

20. Snape, Christopher. Applications of the coupled cluster method to pairing problems.

Degree: PhD, 2010, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/applications-of-the-coupled-cluster-method-to-pairing-problems(c6d69fd0-25cf-4693-ba91-96872c11fc6d).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515111

► The phenomenon of pairing in atomic and nuclear many-body systems gives rise to a great number of different physical properties of matter, from areas as… (more)

Subjects/Keywords: 539.7; Normal Extended Coupled Cluster Method; Quartic Anharmonic Oscillator; Double Well Anharmonic Oscillator; SU(2) quasi spin pairing; BCS theory; BCS BEC Crossover; Ultracold Fermi Atom Gas; CCM; NCCM; ECCM

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

APA (6^th Edition):

Snape, C. (2010). Applications of the coupled cluster method to pairing problems. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/applications-of-the-coupled-cluster-method-to-pairing-problems(c6d69fd0-25cf-4693-ba91-96872c11fc6d).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515111

Chicago Manual of Style (16^th Edition):

Snape, Christopher. “Applications of the coupled cluster method to pairing problems.” 2010. Doctoral Dissertation, University of Manchester. Accessed January 19, 2021. https://www.research.manchester.ac.uk/portal/en/theses/applications-of-the-coupled-cluster-method-to-pairing-problems(c6d69fd0-25cf-4693-ba91-96872c11fc6d).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515111.

MLA Handbook (7^th Edition):

Snape, Christopher. “Applications of the coupled cluster method to pairing problems.” 2010. Web. 19 Jan 2021.

Vancouver:

Snape C. Applications of the coupled cluster method to pairing problems. [Internet] [Doctoral dissertation]. University of Manchester; 2010. [cited 2021 Jan 19]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/applications-of-the-coupled-cluster-method-to-pairing-problems(c6d69fd0-25cf-4693-ba91-96872c11fc6d).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515111.

Council of Science Editors:

Snape C. Applications of the coupled cluster method to pairing problems. [Doctoral Dissertation]. University of Manchester; 2010. Available from: https://www.research.manchester.ac.uk/portal/en/theses/applications-of-the-coupled-cluster-method-to-pairing-problems(c6d69fd0-25cf-4693-ba91-96872c11fc6d).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515111

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