Quantum-Monte-Carlo Calculations for Bosons in a Two-Dimensional Harmonic Trap

TL;DR

This paper uses Path-Integral-Monte-Carlo simulations to study a 2D interacting Bose system in a harmonic trap, analyzing density, condensate, and superfluid properties, highlighting finite-size effects and interaction-induced depletion.

Contribution

It provides detailed Monte Carlo calculations of 2D trapped bosons, revealing finite-size effects and interaction impacts on condensate and superfluid properties.

Findings

Finite-size effects influence density profiles.

Interactions cause condensate depletion.

Significant ground state occupation at low temperatures.

Abstract

Path-Integral-Monte-Carlo simulation has been used to calculate the properties of a two-dimensional (2D) interacting Bose system. The bosons interact with hard-core potentials and are confined to a harmonic trap. Results for the density profiles, the condensate fraction, and the superfluid density are presented. By comparing with the ideal gas we easily observe the effects of finite size and the depletion of the condensate because of interactions. The system is known to have no phase transition to a Bose-Einstein condensation in 2D, but the finite system shows that a significant fraction of the particles are in the lowest state at low temperatures.