Bosonization and entanglement spectrum for one-dimensional polar bosons on disordered lattices

TL;DR

This paper investigates the phase diagram of disordered one-dimensional polar bosons using bosonization and entanglement spectrum analysis, revealing multiple insulating and superfluid phases influenced by disorder type.

Contribution

It introduces a bosonization approach to determine phase boundaries and demonstrates the entanglement spectrum as an effective tool for identifying phases in disordered systems.

Findings

Identification of Mott-insulator, Haldane insulator, superfluid, and Bose glass phases.

Entanglement spectrum effectively indicates different quantum phases.

Quasiperiodic potential introduces additional incommensurate density wave phase.

Abstract

The extended Bose-Hubbard model subjected to a disordered potential is predicted to display a rich phase diagram. In the case of uniform random disorder one finds two insulating quantum phases -- the Mott-insulator and the Haldane insulator -- in addition to a superfluid and a Bose glass phase. In the case of a quasiperiodic potential further phases are found, eg the incommensurate density wave, adiabatically connected to the Haldane insulator. For the case of weak random disorder we determine the phase boundaries using a perturbative bosonization approach. We then calculate the entanglement spectrum for both types of disorder, showing that it provides a good indication of the various phases.