Non-adiabatic dynamics across a first order quantum phase transition: Quantized bubble nucleation

TL;DR

This paper investigates the non-adiabatic dynamics of a quantum Ising chain during a first order quantum phase transition, revealing quantized bubble nucleation via Landau-Zener transitions and multiple metastability loss stages.

Contribution

It introduces a detailed analysis of quantized bubble nucleation and metastability loss in quantum phase transitions, linking dynamics to Landau-Zener theory.

Findings

Multiple regions where metastability is lost in stages

Resonant tunneling to specific bubble sizes identified

Landau-Zener transitions quantitatively predict nucleation probabilities

Abstract

Metastability is a quintessential feature of first order quantum phase transitions, which is lost either by dynamical instability or by nucleating bubbles of a true vacuum through quantum tunneling. By considering a drive across the first order quantum phase transition in the quantum Ising chain in the presence of both transverse and longitudinal fields, we reveal multiple regions in the parameter space where the initial metastable state loses its metastability in successive stages. The mechanism responsible is found to be semi-degenerate resonant tunnelings to states with specific bubble sizes. We show that such dynamics of quantized bubble nucleations can be understood in terms of Landau-Zener transitions, which provide quantitative predictions of nucleation probabilities for different bubble sizes.