Energy spectrum and phase diagrams of two-sublattice hard-core boson model

TL;DR

This paper analyzes the energy spectrum and phase diagrams of a two-sublattice hard-core boson model, revealing how temperature, chemical potential, and sublattice energy differences influence phase transitions and spectrum reconstruction.

Contribution

It provides a detailed analysis of the energy spectrum and phase diagrams of the two-sublattice hard-core boson model using the random phase approximation, including spectrum reconstruction and phase boundary determination.

Findings

Reconstruction of boson spectrum with changing temperature and parameters

Identification of phase regions including MI, CDW, and SF phases

Phase diagrams illustrating phase coexistence and transitions

Abstract

The energy spectrum, spectral density and phase diagrams have been obtained for two-sublattice hard-core boson model in frames of random phase approximation approach. Reconstruction of boson spectrum at the change of temperature, chemical potential and energy difference between local positions in sublattices is studied. The phase diagrams illustrating the regions of existence of a normal phase which can be close to Mott-insulator (MI) or charge-density (CDW) phases as well as the phase with the Bose-Einstein condensate (SF phase) are built.