2009/07/01 by J. M. Diederix, Diederix, J. M., K. B. Gubbels +3
Physics and Astronomy · #FOS: Physical sciences #Quantum Gases (cond-mat.quant-gas) #Statistical Mechanics (cond-mat.stat-mech) #cond-mat.quant-gas #cond-mat.stat-mech
paper · pdf · doi:10.48550/arxiv.0907.0127
12 pages, 9 figures, Large extension with an extra part on Bogoliubov-de Gennes
arxiv created 2009/12/11 · arxiv updated 2010/01/07
We present an inhomogeneous theory for the low-temperature properties of a resonantly interacting Fermi mixture in a trap that goes beyond the local-density approximation. We compare the Bogoliubov-de Gennes and a Landau-Ginzburg approach and conclude that the latter is more appropriate when dealing with a first-order phase transition. Our approach incorporates the state-of-the-art knowledge on the homogeneous mixture with a population imbalance exactly and gives good agreement with the experimental density profiles of Shin \it et al. [Nature \bf 451, 689 (2008)]. We calculate the universal surface tension due to the observed interface between the equal-density superfluid and the partially polarized normal state of the mixture. We find that the exotic and gapless superfluid Sarma phase can be stabilized at this interface, even when this phase is unstable in the bulk of the gas.