Fermion-mediated interactions in a dilute Bose-Einstein condensate
Abstract
We develop a diagrammatic perturbation treatment to calculate the zero-temperature equation of state of the dilute gas mixture of a single spin component Bose-Einstein condensate (BEC) and a normal Fermi gas of indistinguishable (single spin) fermion particles. We find that the mean-field description breaks down near the mechanical instability related to the phase separation phenomenon. Our analysis shows that the instability is caused by the competition of the usual short-range and fermion-mediated boson-boson interactions, which result in a boson compressibility that diverges. In the low BEC-density limit, we show that the diagrammatic analysis simplifies, we sum part of the higher order diagrams, and we discuss the effects of other higher-order contributions.
Cite
@article{arxiv.0806.0598,
title = {Fermion-mediated interactions in a dilute Bose-Einstein condensate},
author = {D. H. Santamore and Eddy Timmermans},
journal= {arXiv preprint arXiv:0806.0598},
year = {2009}
}
Comments
16 pages, 6 figures, typo corrected