Light-cone like spreading of single-particle correlations in the Bose-Hubbard model after a quantum quench in the strong coupling regime

TL;DR

This paper investigates how single-particle correlations spread in the Bose-Hubbard model after a quantum quench, revealing light-cone like dynamics across different dimensions using a novel equations of motion approach.

Contribution

The authors derive equations of motion for the single-particle Green's function in the strong coupling regime, enabling analysis of correlation dynamics post-quench.

Findings

Light-cone like spreading of correlations observed in 1D, 2D, and 3D.

Propagation velocities of correlations calculated for each dimension.

Method applicable to strong coupling regimes in Bose-Hubbard model.

Abstract

We study the spreading of correlations in space and time after a quantum quench in the Bose Hubbard model. We derive equations of motion for the single-particle Green's function within the contour-time formalism, allowing us to study dynamics in the strong coupling regime. We discuss the numerical solutions of these equations and calculate the single-particle density matrix for quenches in the Mott phase. We demonstrate light-cone like spreading of correlations in the Mott phase in one, two, and three dimensions and calculate propagation velocities in each dimension.