Out-of-equilibrium dynamics of Bose-Bose mixtures in optical lattices

TL;DR

This paper studies the out-of-equilibrium dynamics of two-component Bose mixtures in optical lattices during quantum phase transitions, revealing unique behaviors and critical phenomena distinct from single-component systems.

Contribution

It provides the first detailed analysis of quench dynamics across both first- and second-order MI-SF transitions in Bose-Bose mixtures, including critical slowing down and scaling laws.

Findings

Bose mixtures exhibit different quantum dynamics than single-component gases.

Critical slowing down occurs near the transition point, consistent with Kibble-Zurek mechanism.

Numerical critical exponents match mean-field predictions.

Abstract

We examine the quench dynamics across quantum phase transitions from a Mott insulator (MI) to a superfluid (SF) phase in a two-component bosonic mixture in an optical lattice. We show that two-component Bose mixtures exhibit qualitatively different quantum dynamics than one-component Bose gas. Besides second-order MI-SF transitions, we also investigate quench dynamics across a first-order MI-SF transition. The Bose mixtures show the critical slowing down of dynamics near the critical transition point, as proposed by the Kibble-Zurek mechanism. For MI-SF transitions with homogeneous lattice-site distributions in the MI phase, the dynamical critical exponents extracted by the power-law scaling of the proposed quantities obtained via numerical simulations are in very close agreement with the mean-field predictions.