1.

Record Nr.

UNISA996418432303316

Autore

Nagao Kazuma

Titolo

Fluctuations and Non-Equilibrium Phenomena in Strongly-Correlated Ultracold Atoms [[electronic resource] /] / by Kazuma Nagao

Pubbl/distr/stampa

Singapore : , : Springer Singapore : , : Imprint : Springer, , 2020

ISBN

981-15-7171-6

Edizione

[1st ed. 2020.]

Descrizione fisica

1 online resource (126 pages)

Collana

Springer Theses, Recognizing Outstanding Ph.D. Research, , 2190-5053

Disciplina

530.43078

Soggetti

Phase transformations (Statistical physics)

Condensed materials

Superconductivity

Superconductors

Phase transitions (Statistical physics)

Statistical physics

Quantum Gases and Condensates

Strongly Correlated Systems, Superconductivity

Phase Transitions and Multiphase Systems

Statistical Physics and Dynamical Systems

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di contenuto

Introduction -- Ultracold Bose Gases in Optical Lattices -- Phase Space Methods for Quantum Dynamics -- Response of the Higgs Mode in a Three Dimensional Optical Lattice -- Semiclassical Quench Dynamics of Bose Gases in Optical Lattices -- Conclusions and Outlooks -- Appendix.

Sommario/riassunto

This book discusses non-equilibrium quantum many-body dynamics, recently explored in an analog quantum simulator of strongly correlated ultracold atoms. The first part presents a field-theoretical analysis of the experimental observability of the Higgs amplitude mode that emerges as a relativistic collective excitation near a quantum phase transition of superfluid Bose gases in an optical lattice potential. The author presents the dynamical susceptibilities to external driving of the microscopic parameters, taking into account a leading-order



perturbative correction from quantum and thermal fluctuations and shows clear signatures of the Higgs mode in these observables. This is the first result that strongly supports the stability of the Higgs mode in three-dimensional optical lattices even in the presence of a spatially inhomogeneous confinement potential and paves the way for desktop observations of the Higgs mode. In the second part, the author applies the semi-classical truncated-Wigner approximation (TWA) to far-from-equilibrium quantum dynamics. Specifically, he considers the recent experiments on quantum-quench dynamics in a Bose-Hubbard quantum simulator. A direct comparison shows remarkable agreement between the numerical results from TWA and the experimental data. This result clearly indicates the potential of such a semi-classical approach in reliably simulating many-body systems using classical computers. The book also includes several chapters providing comprehensive reviews of the recent studies on cold-atomic quantum simulation and various theoretical methods, including the Schwinger-boson approach in strongly correlated systems and the phase-space semi-classical method for far-from-equilibrium quantum dynamics. These chapters are highly recommended to students and young researchers who are interested in semi-classical approaches in non-equilibrium quantum dynamics.