Quasiadiabatic dynamics of ultracold bosonic atoms in a one-dimensional optical superlattice

TL;DR

This paper investigates the slow dynamics of ultracold bosonic atoms in a one-dimensional optical superlattice, revealing defect formation and scaling laws related to the Kibble-Zurek mechanism during phase transitions.

Contribution

It introduces a detailed analysis of defect formation during quasiadiabatic ramps across different quantum phases in a superlattice, highlighting nontrivial scaling behaviors.

Findings

Defects depend on the quench velocity following a power-law.

Scaling of defects varies with the width of the superfluid region.

A Kibble-Zurek-like mechanism is observed for intermediate quench rates.

Abstract

We study the quasiadiabatic dynamics of a one-dimensional system of ultracold bosonic atoms loaded in an optical superlattice. Focusing on a slow linear variation in time of the superlattice potential, the system is driven from a conventional Mott insulator phase to a superlattice-induced Mott insulator, crossing in between a gapless critical superfluid region. Due to the presence of a gapless region, a number of defects depending on the velocity of the quench appear. Our findings suggest a power-law dependence similar to the Kibble-Zurek mechanism for intermediate values of the quench rate. For the temporal ranges of the quench dynamics that we considered, the scaling of defects depends nontrivially on the width of the superfluid region.