p -wave superfluidity in mixtures of ultracold Fermi and spinor Bose gases

Abstract

We reveal that the p-wave superfluid can be realized in a mixture of fermionic and F=1 bosonic gases. We derive a general set of the gap equations for gaps in the s-and p-channels. It is found that the spin-spin bose-fermi interactions favor the p-wave pairing and naturally suppress the pairing in the s-channel. The gap equations for the polar phase of p-wave superfluid fermions are numerically solved. It is shown that a pure p-wave superfluid can be observed in a well-controlled environment of atomic physics.

s- and p-superfluidity of Fermi atoms in Bose-Fermi mixtures

“…Although we demonstrated in Ref. [23] that the polar p-wave phase can be realized, its competition with the s-wave state was left as an open question.…”

“…The operator nB (r) = m Ψ+ m (r) Ψm (r), m ∈ {−1, 0, +1} denotes the number density for bosonic fields. As to the ultracold gas of spin-1 bosonic atoms, we consider in this paper 23 Na atoms in the polar spinor Bose-Einstein condensate (BEC) state with c 2 /c 0 = 6.25 • 10 −2 and a…”

“…where σj are the Pauli-matrices for spin-1 2 fermions. To be specific, we fix in our study the fermionic and bosonic densities n F = n B = 10 14 cm −3 for 40 K and 23 Na atoms that gives the Fermi energy…”

“…Although we concentrate in this paper on the s-wave state, it is useful to present here the details of the derivation of the p-wave gap equation obtained in Ref. [23]. Setting ω k = ω 0 = πk B T / in Eq.…”

“…A spinor Bose-Einstein condensate (BEC) supports various types of excitations not available in single-component BECs, which offers considerable scope for the realization of unconventional superfluid states of quantum gases. In our recent paper [23], we analyzed the p-wave polar phase in mixtures of ultracold Fermi and F = 1 Bose gases. It was found that the spin-induced interactions in a mixture of spinor atomic BEC and fermionic atoms naturally suppress the s-wave pairing.…”