Induced $p$-wave pairing in Bose-Fermi mixtures

TL;DR

This paper develops a strong coupling theory for $p$-wave pairing in Bose-Fermi mixtures, revealing conditions under which such superfluidity can be experimentally realized, emphasizing the importance of retardation and self-energy effects.

Contribution

It introduces a comprehensive self-consistent theory for $p$-wave pairing in Bose-Fermi mixtures, accounting for full frequency and momentum dependence of the induced interaction, and identifies optimal experimental parameters.

Findings

Retardation and self-energy effects are crucial for accurate critical temperature estimates.

Light bosons and heavy fermions are most suitable for realizing $p$-wave superfluidity.

Experimental realization of $p$-wave superfluidity in Bose-Fermi mixtures is feasible.

Abstract

Cooper pairing caused by an induced interaction represents a paradigm in our description of fermionic superfluidity. Here, we present a strong coupling theory for the critical temperature of $p$-wave pairing between spin polarised fermions immersed in a Bose-Einstein condensate. The fermions interact via the exchange of phonons in the condensate, and our self-consistent theory takes into account the full frequency/momentum dependence of the resulting induced interaction. We demonstrate that both retardation and self-energy effects are important for obtaining a reliable value of the critical temperature. Focusing on experimentally relevant systems, we perform a systematic analysis varying the boson-boson and boson-fermion interaction strength as well as their masses, and identify the most suitable system for realising a $p$-wave superfluid. Our results show that such a superfluid indeed is experimentally within reach using light bosons mixed with heavy fermions.