Experimentally accessible reentrant phase transitions in double-well optical lattices

TL;DR

This paper investigates reentrant quantum phase transitions in bosonic systems within double-well optical lattices, demonstrating their persistence even with trapping potentials and proposing experimental detection methods.

Contribution

It reveals the occurrence of reentrant Mott insulator to superfluid phase transitions in double-well optical lattices with traps, using advanced simulation techniques.

Findings

Reentrant phase transition observed at unit filling.

Transition persists despite the presence of a parabolic trap.

Experimental detection via matter-wave interference suggested.

Abstract

We study the quantum phases of bosons confined in a combined potential of a one-dimensional double-well optical lattice and a parabolic trap. We apply the time-evolving block decimation method to the corresponding two-legged Bose-Hubbard model. In the absence of a parabolic trap, the system of bosons in the double-well optical lattice exhibits a reentrant quantum phase transition between Mott insulator and superfluid phases at unit filling as the tilt of the double-wells is increased. We show that the reentrant phase transition occurs also in the presence of a parabolic trap and suggest that it can be detected in experiments by measuring the matter-wave interference pattern.