Analytic calculation of high order corrections to quantum phase transitions of ultracold Bose gases in bipartite superlattices

TL;DR

This paper improves the generalized effective-potential Landau theory to analytically calculate high-order corrections to quantum phase transitions in ultracold Bose gases within bipartite superlattices, achieving results that align well with quantum Monte Carlo simulations.

Contribution

The paper refines the GEPLT method and applies it to analytically determine quantum phase boundaries up to third-order hopping in ultracold Bose gases.

Findings

Analytical quantum phase boundaries match QMC results.

Third-order hopping corrections improve accuracy.

Clarified GEPLT enhances theoretical consistency.

Abstract

We clarify some technical issues in the present generalized effective-potential Landau theory (GEPLT) that makes the GEPLT more consistent and complete. Utilizing this clarified GEPLT, we analytically study the quantum phase transitions of ultracold Bose gases in bipartite superlattices at zero termparture. The corresponding quantum phase boundaries are analytically calculated up to the third-order hopping, which are in excellent agreement with the quantum Monte Carlo (QMC) simulations.