Real time confinement following a quantum quench to a non-integrable model

TL;DR

This paper investigates how confinement of elementary excitations in a non-integrable quantum spin chain suppresses the typical light-cone spreading of correlations after a quench, offering a new mechanism to control non-equilibrium dynamics.

Contribution

It introduces a confinement-based mechanism to strongly suppress correlation spreading in non-integrable quantum systems, extending the concept of confinement from particle physics to condensed matter.

Findings

Confinement suppresses light-cone spreading in the Ising chain.

The mechanism is general and applicable to other systems.

Potential for experimental observation in cold atom setups.

Abstract

Light cone spreading of correlations and entanglement is a key feature of the non-equilibrium quench dynamics of many-body quantum systems. First proposed theoretically, it has been experimentally revealed in cold-atomic gases and it is expected to be a generic characteristic of any quench in systems with short-range interactions and no disorder. Conversely, here we propose a mechanism that, through confinement of the elementary excitations, strongly suppresses the light-cone spreading. Confinement is a celebrated concept in particle physics, but it also exists in condensed matter systems, most notably in one spatial dimension where it has been experimentally observed. Our results are obtained for the Ising spin chain with transverse and longitudinal magnetic field, but the proposed mechanism is of general validity since it is based on the sole concept of confinement and it should be easily observed in cold atom experiments.