Harmonically trapped Bose-Bose mixtures: a quantum Monte Carlo study

TL;DR

This study uses quantum Monte Carlo methods to analyze harmonically trapped Bose-Bose mixtures, comparing results with mean-field predictions and exploring the effects of interaction strengths and mass asymmetry on system behavior.

Contribution

It provides a detailed quantum Monte Carlo analysis of Bose-Bose mixtures, highlighting deviations from mean-field theory and revealing universal behaviors beyond traditional approximations.

Findings

Density profiles differ significantly from mean-field predictions.

Miscibility criterion applies well but shows discrepancies near phase separation.

Results demonstrate universality beyond Gross-Pitaevskii applicability.

Abstract

We study a harmonically confined Bose-Bose mixture using quantum Monte Carlo methods. Our results for the density profiles are systematically compared with mean-field predictions derived through the Gross-Pitaevskii equation in the same conditions. The phase space as a function of the interaction strengths and the relation between masses is quite rich. The miscibility criterion for the homogeneous system applies rather well to the system, with some discrepancies close to the critical line for separation. We observe significant differences between the mean-field results and the Monte Carlo ones, that magnify when the asymmetry between masses increases. In the analyzed interaction regime, we observe universality of our results which extend beyond the applicability regime for the Gross-Pitaevskii equation.