Interacting Quantum Systems Out of Equilibrium (0121)
May 05, 2016 – May 06, 2016
Douglas Natelson, Rice University
Junichiro Kono, Rice University
Matthew Foster, Rice University
Kaden Hazzard, Rice University
A frontier topic in physics today is the understanding of correlated quantum many-body systems driven out of equilibrium. This is a broad, highly active area, with advancements coming through the development of new experimental and theoretical techniques. The competition between different ordered phases leads to dramatic effects (high temperature superconductivity; quantum magnetism; quantum phase transitions; spontaneous breaking of multiple symmetries) even when considering the ground state. Considering such systems out of equilibrium raises issues of nonequilibrium transitions such as many-body localization; order parameter dynamics during and after a “quench”; thermalization and the approach to steady state; and transport in the presence of a strong driving potential.
Ultracold atom systems are proving to be excellent tools for studying certain problems (thanks to the ability to probe microscopic details of distributions directly). Electronic bias beyond the linear regime and optical pump/probe experiments are established methods of examining quantum materials and systems to probe their steady-state and dynamic responses. While local quench dynamics have long appeared in quantum materials physics in the guise of Fermi edge singularities, both ultracold atom and ultrafast pump-probe spectroscopy experiments have very recently opened up a completely new field of far-from-equilibrium research: coherent quantum many-body dynamics following a global quench. Quench dynamics relate to fundamental questions in statistical physics such as the thermalization of an isolated many-particle system, quantum versus classical chaos and dissipation, and many-body localization.
The potential technological impact for driven quantum systems is transformative. Recent progress suggests that proper driving perturbations can drastically alter the effective electronic structure of appropriate materials, producing dramatic changes in their properties, such as the emergence of superconducting order or topologically nontrivial states. Control over dissipation and irreversibility in such systems could lead eventually to device applications with novel functionality or greatly reduced power consumption.