arXiv:cond-mat/0605751 · Physical Review A

Universal phase diagram of a strongly interacting Fermi gas with unbalanced spin populations

Frédéric Chevy

Published Dec 29, 2006• 416 citations

Abstract

We present a theoretical interpretation of a recent experiment presented by Zwierlein et al. [Nature (London) 442, 54 (2006)] on the density profile of Fermi gases with unbalanced spin populations. We show that in the regime of strong interaction, the boundaries of the three phases observed by Zwierlein et al. can be characterized by two dimensionless numbers ${\ensuremath{\eta}}_{\ensuremath{\alpha}}$ and ${\ensuremath{\eta}}_{\ensuremath{\beta}}$. Using a combination of a variational treatment and a study of the experimental results, we infer rather precise bounds for these two parameters.

DOI: 10.1103/physreva.74.063628

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arXiv:cond-mat/0605751 · Physical Review A

Universal phase diagram of a strongly interacting Fermi gas with unbalanced spin populations

Frédéric Chevy

Published Dec 29, 2006• 416 citations

arXiv HTML PDF

Abstract

{\ensuremath{\eta}}_{\ensuremath{\alpha}}

and

{\ensuremath{\eta}}_{\ensuremath{\beta}}

. Using a combination of a variational treatment and a study of the experimental results, we infer rather precise bounds for these two parameters.

DOI: 10.1103/physreva.74.063628

Related papers

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Physical Review LettersApr 4, 2006102 citations

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{\ensuremath{\eta}}_{\ensuremath{\alpha}}

and

{\ensuremath{\eta}}_{\ensuremath{\beta}}

. Using a combination of a variational treatment and a study of the experimental results, we infer rather precise bounds for these two parameters.

We obtain the phase diagram of spin-imbalanced interacting Fermi gases from measurements of density profiles of

^{6}\mathrm{Li}

atoms in a harmonic trap. These results agree with, and extend, previous experimental measurements. Measurements of the critical polarization at which the balanced superfluid core vanishes generally agree with previous experimental results and with quantum Monte Carlo (QMC) calculations in the Bardeen-Cooper-Schrieffer and unitary regimes. We disagree with the QMC results in the Bose-Einstein condensate regime, however, where the measured critical polarizations are greater than theoretically predicted. We also measure the equation of state in the crossover regime for a gas with equal numbers of the two fermion spin states.