Statistical properties of cold bosons in a ring trap

TL;DR

This paper investigates the statistical properties of cold bosons in a ring trap, analyzing coherence, fluctuations, and density behavior at finite temperatures using classical fields approximation and exact calculations for ideal gases.

Contribution

It provides new insights into the coherence length, ground state population, and density fluctuations of bosons with contact and dipolar interactions in a ring trap at finite temperature.

Findings

Coherence length and ground state population depend on temperature.

Density fluctuations are characterized for attractive bosons.

Partition function for ideal gas is exactly calculated.

Abstract

A study of an interacting system of bosons in a ring trap at a finite temperature is presented. We consider a gas with contact and long-range dipolar interactions within a framework of the classical fields approximation. For a repulsive gas we have obtained coherence length, population of the ground state and its fluctuations as a function of temperature. In the case of an attractive gas we study local density fluctuations. Additionally, we exactly calculate the partition function for the ideal gas in the canonical ensemble and derive several other macroscopic state functions.