Deconfinement and phase diagram of bosons in a linear optical lattice with a particle reservoir

TL;DR

This paper explores the phase diagram of bosons in a 1D optical lattice coupled to a particle reservoir, revealing phases of phase-locking, vortex deconfinement, and Mott insulation through renormalization group analysis.

Contribution

It introduces a detailed phase diagram for bosons in a 1D lattice with reservoir coupling, highlighting the transition mechanisms and phases.

Findings

Identifies three distinct phases: phase-locked, vortex-deconfined, and Mott insulator.

Shows quantum fluctuations induce vortex deconfinement and metallic behavior.

Demonstrates the impact of reservoir coupling on the phase transitions.

Abstract

We investigate the zero-temperature phases of bosons in a one-dimensional optical lattice with an explicit tunnel coupling to a Bose condensed particle reservoir. Renormalization group analysis of this system is shown to reveal three phases: one in which the linear system is fully phase-locked to the reservoir; one in which Josephson vortices between the one-dimensional system and the particle reservoir deconfine due to quantum fluctuations, leading to a decoupled state in which the one-dimensional system is metallic; and one in which the one-dimensional system is in a Mott insulating state.