paper

Quench dynamics of quasi-periodic systems exhibiting Rabi oscillations of two-level integrals of motion

arXiv:2106.09384 · doi:10.1016/j.aop.2021.168545

Abstract

The elusive nature of localized integrals of motion (or l-bits) in disordered quantum systems lies at the core of some of their most prominent features, i.e. emergent integrability and lack of thermalization. Here, we study the quench dynamics of a one-dimensional model of spinless interacting fermions in a quasi-periodic potential with a localization-delocalization transition. Starting from an unentangled initial state, we show that in the strong disorder regime an important subset of the -bits can be explicitly identified with strongly localized two-level systems, associated with particles confined on two lattice sites. The existence of such subsystems forming an ensemble of nearly free l-bits is found to dominate the short-time dynamics of experimentally relevant quantities, such as the Loschmidt echo and the particle imbalance. We investigate the importance of the choice of the initial state by developing a second quench protocol, starting from the ground-state of the model at different initial disorder strengths and monitoring the quench dynamics close to the delicate ETH-MBL transition regime.

15 pages, 5 Figures. Submitted to the 2020 Localization Special Issue of Annals of Physics

References in corpus (15)

Quench dynamics of quasi-periodic systems exhibiting Rabi oscillations of two-level integrals of motion · wovepaper