Nonadiabatic Phase Transition with Broken Chiral Symmetry

TL;DR

This paper investigates nonadiabatic quantum phase transitions in an Ising spin chain with broken chiral symmetry, revealing a mechanism for exponential quasiparticle density separation during nearly-adiabatic evolution.

Contribution

It introduces a novel analysis of nonadiabatic transitions in a chiral-symmetry-broken Ising chain, showing suppressed excitations and exponential quasiparticle density separation.

Findings

Excitations on one sub-lattice are exponentially suppressed in the nearly-adiabatic regime.

A coherent mechanism for exponential quasiparticle density separation is identified.

The study advances understanding of nonadiabatic transitions in complex spin systems.

Abstract

We explore nonadiabatic quantum phase transitions in an Ising spin chain with a linearly time-dependent transverse field and two different spins per unit cell. Such a spin system passes through critical points with gapless excitations, which support nonadiabatic transitions. Nevertheless, we find that the excitations on one of the chain sub-lattices are suppressed in the nearly-adiabatic regime exponentially. Thus, we reveal a coherent mechanism to induce exponentially large density separation for different quasiparticles.