Berislav Buča: Dynamical l-bits in Stark many-body localization

Stark many-body localized (SMBL) systems have been shown both numerically and experimentally to have Bloch many-body oscillations, quantum many-body scars, and fragmentation in the large field tilt limit. Likewise, they are believed to show localization similar to disordered MBL. I will discuss how all of these observations can be analytically understood by rigorously showing the existence of novel algebraic structures that are exponentially stable in time in the large tilt limit. I call this novel operators dynamical l-bits. Moreover, I show that many-body Bloch oscillations persist even at infinite temperature for exponentially long-times. I provide numerical confirmation of these results by studying the prototypical Stark MBL model of a tilted XXZ spin chain. The work explains why thermalization was observed in a recent 2D tilted experiment. As dynamical l-bits are stable, localized and quantum coherent excitations, the work opens new possibilities for quantum information processing in Stark MBL systems.

Reference: T. Gunawardana, B. Buča. Dynamical l-bits in Stark many-body localization. arXiv:2110.13135 (2021)