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Journal of Experimental and Theoretical Physics Letters

On the possibility of a superfluid transition in a Fermi gas of neutral particles at ultralow temperatures

M. A. Baranov, Yu. Kagan, M. Yu. Kagan

Published Aug 1, 1996• 75 citations
Publisher

Abstract

The possibility of triplet Cooper pairing in a Fermi gas of neutral particles in magnetic traps at ultralow temperatures is predicted. Estimates are presented for the superfluid transition temperature.
DOI
10.1134/1.567187

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The Fermi-liquid approach generalized to superfluid systems is used to derive general formulas for the normal and abnormal distribution functions (DF) for quasiparticles of a superfluid Fermi liquid (SFL) consisting of electrically neutral fermions with spin-triplet pairing (the spin of a pair s=1, the orbital angular momentum l of the pair being an arbitrary odd number) in a static uniform magnetic field, taking into account the Landau spin-exchange Fermi-liquid interaction at temperatures 0<T<Tc (Tc is the temperature of phase transition from the normal to the superfluid state). In deriving the DF, the explicit form of the energy functional (EF) for SFL is not used. A system of coupled equations is obtained for the order parameter, energy of quasiparticles, and effective magnetic field for the SFL under investigation in the case of an EF quadratic in DF. The obtained DF and the system of equations are applicable for describing both unitary and nonunitary phases of superfluid He3 in a magnetic field, e.g., for determining the magnetization and magnetic susceptibility of these phases.