Physics (Internal)

Slow dynamics in and around many-body localized states

This event is part of the Biophysics/Condensed Matter Seminar Series.

Abstract: Isolated quantum systems subject to disorder can enter a "many-body localized" (MBL) phase in which they do not come to local thermal equilibrium under their intrinsic dynamics. The transition between the MBL phase and the more familiar "ergodic" phase -- in which the system does come to local thermal equilibrium -- is intrinsically unconventional, as it is a transition where equilibrium statistical mechanics itself breaks down. The dynamics of relaxation and response in the MBL phase are governed by rare resonant configuration pairs and by rare locally thermal clusters; the former mechanism is dominant deep in the MBL phase and the latter is dominant near the delocalization transition. I will discuss these mechanisms, which give rise to highly heterogeneous dynamics within the MBL phase, and then introduce signatures of the corresponding heterogeneous and slow dynamics in the ergodic phase near the MBL transition.