Localized dynamics following a quantum quench in a non-integrable system: An example on the sawtooth ladder

TL;DR

This paper investigates how certain initial states in a non-integrable sawtooth ladder system exhibit localization-like behavior, such as memory retention and slow entanglement growth, despite the system's overall thermalization.

Contribution

It demonstrates the existence of localized dynamics in a non-integrable system due to interaction-induced quantum interference, expanding understanding of ergodicity breaking.

Findings

Localization persists in a thermalizing spectrum

Initial state memory retention observed

Slow entanglement entropy growth

Abstract

Motivated by the recent discovery of ergodicity breaking in geometrically frustrated systems, we study the quench dynamics of interacting hardcore bosons on a sawtooth ladder. We identify a set of initial states for which this system exhibits characteristic signatures of localization like initial state memory retention and slow growth of entanglement entropy for a wide parameter regime. Remarkably, this localization persists even when the many-body spectrum is thermalizing. We argue that the localized dynamics originates from an interaction induced quantum interference. Our results show that the sawtooth ladder can be a fertile platform for realizing non-equilibrium quantum states of matter.