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BCS to BEC Quantum Phase Transition in Spin Polarized Fermionic Gases

S. S. Botelho·C. A. R. Sá de Melo
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Abstract

We discuss the possibility of a quantum phase transition in ultracold spin polarized fermionic gases which exhibit a p-wave Feshbach resonace. We show that when fermionic atoms form a condensate that can be externally tuned between the BCS and BEC limits, the zero temperature compressibility and the spin susceptibility of the fermionic gas are non-analytic functions of the two-body bound state energy. This non-analyticity is due to a massive rearrangement of the momentum distribution in the ground state of the system. Furthermore, we show that the low temperature superfluid density is also non-analytic, and exibits a dramatic change in behavior when the critical value of the bound state energy is crossed.

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S. S. Botelho, C. A. R. Sá de Melo. 2004-09-14. BCS to BEC Quantum Phase Transition in Spin Polarized Fermionic Gases. https://arxiv.org/abs/cond-mat/0409357

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