Quantum Phase Analysis of Extended Bose-Hubbard Model

TL;DR

This paper maps the quantum phase diagram of a one-dimensional extended Bose-Hubbard model, revealing various phases and phase transitions using advanced computational methods, emphasizing the importance of extended interactions.

Contribution

It provides the first detailed phase diagram for the extended Bose-Hubbard model using DMRG and bosonization, highlighting the role of extended interactions in phase boundaries.

Findings

Direct transition from Mott insulator to superconductor at integer fillings

Presence of two types of repulsive Luttinger liquids at half-integer fillings

Extended interactions are essential for accurate phase boundary determination

Abstract

We have obtained the quantum phase diagram of one dimensional extended Bose-Hubbard model using the density-matrix renormalization group and Abelian bosonization methods for different commensurabilities. We describe the nature of different quantum phases at the charge degeneracy point. We find a direct phase transition from Mott insulating phase to superconducting phase for integer band fillings of bosons. We predict explicitly the presence of two kinds of repulsive Luttinger liquid phases, apart from the charge density wave and superconducting phases for half-integer band fillings. Our study reveals that extended range interactions are necessary to get the correct phase boundary of an one-dimensional interacting bosons system.