Loschmidt Amplitude and Work Distribution in Quenches of the Sine-Gordon Model

TL;DR

This paper investigates the non-equilibrium dynamics of the Sine-Gordon model after quantum quenches, calculating exact Loschmidt amplitudes and work distributions, revealing universal features and dualities across interaction regimes.

Contribution

It provides the first exact calculations of Loschmidt amplitude and work distribution for quenches in the Sine-Gordon model using Bethe Ansatz, highlighting universal behaviors and dualities.

Findings

Exact Loschmidt amplitude and work distribution computed for various interaction strengths.

Identification of universal features in quench dynamics.

Discovery of a duality relating different parameter regimes.

Abstract

The Sine-Gordon - equivalently, the massive Thirring - Hamiltonian is ubiquitous in low-dimensional physics, with applications that range from cold atom and strongly correlated systems to quantum impurities. We study here its non-equilibrium dynamics using the quantum quench protocol - following the system as it evolves under the Sine-Gordon Hamiltonian from initial Mott type states with large potential barriers. By means of the Bethe Ansatz we calculate exactly the Loschmidt amplitude, the fidelity and work distribution characterizing these quenches for different values of the interaction strength. Some universal features are noted as well as an interesting duality relating quenches in different parameter regimes of the model.