On the Functional Integral Theory of Systems with Kinematical Interaction

TL;DR

This paper develops a functional integral approach to study low-temperature thermodynamics of quantum spin systems with a kinematical constraint on boson occupancy, revealing a temperature-dependent chemical potential.

Contribution

It introduces a systematic method to analyze systems with kinematical interactions using functional integration, accounting for finite boson occupancy constraints.

Findings

Derived the low-temperature asymptotics of the chemical potential.

Established a self-consistent calculation framework for thermodynamic properties.

Highlighted the impact of kinematical constraints on system behavior.

Abstract

We propose a systematic way to investigate the low-temperature thermodynamic properties of quantum spin systems subject to the restriction that only a finite number of bosons may occupy a single lattice site. Such a kinematical interaction results in appearance of a temperature dependent chemical potential. Its low-temperature asymptotics is calculated self-consistently using the functional integration technique.