Quantum Phase Transitions and Heat Capacity in a two-atoms Bose-Hubbard Model

TL;DR

This paper investigates a two-atom Bose-Hubbard model revealing three distinct phases linked to quantum phase transitions, with thermal entanglement and heat capacity behaviors providing insights into these phases.

Contribution

It demonstrates the connection between thermal entanglement, heat capacity, and quantum phase transitions in a two-atom Bose-Hubbard model, highlighting phase distinctions.

Findings

Three phases identified in thermal entanglement behavior.

Heat capacity exhibits similar phase-dependent patterns.

Quantum phase transitions underpin the phase structure.

Abstract

We show that a two-atoms Bose-Hubbard model exhibits three different phases in the behavior of thermal entanglement in its parameter space. These phases are demonstrated to be traceable back to the existence of quantum phase transitions in the same system. Significant similarities between the behaviors of thermal entanglement and heat capacity in the parameter space are brought to light thus allowing to interpret the occurrence and the meaning of all these three phases.