Condensation and interaction range in harmonic boson traps: a variational approach

TL;DR

This paper develops a variational method to analyze how interaction range affects bound states and phase diagrams in a bosonic gas confined in a harmonic trap, using a Feynman-Kac functional approach.

Contribution

It introduces a variational bound for the free energy of interacting bosons in a trap, incorporating the effect of interaction range within a harmonic approximation.

Findings

Interaction range influences the existence of many-particle bound states.

The phase diagram of the bosonic system is affected by the interaction parameters.

A variational estimate provides insights into the system's thermodynamic properties.

Abstract

For a gas of N bosons interacting through a two-body Morse potential a variational bound of the free energy of a confined system is obtained. The calculation method is based on the Feynman-Kac functional projected on the symmetric representation. Within the harmonic approximation a variational estimate of the effect of the interaction range on the existence of many-particle bound states, and on the N-T phase diagram is obtained.