Engineering Superfluidity in Bose-Fermi Mixtures of Ultracold Atoms

TL;DR

This paper explores how to engineer various superfluid phases with different pairing symmetries in ultracold Bose-Fermi mixtures in optical lattices, revealing tunable unconventional superfluidity with measurable transition temperatures.

Contribution

It demonstrates the creation and stability analysis of s-, p-, and d-wave superfluid phases in Bose-Fermi mixtures using mean-field theory, highlighting experimental feasibility.

Findings

Multiple pairing symmetries can be realized by tuning system parameters.

Unconventional superfluids exhibit transition temperatures around 1% of the Fermi energy.

Phase diagrams include superfluid and density wave phases.

Abstract

We investigate many-body phase diagrams of atomic boson-fermion mixtures loaded in the two-dimensional optical lattice. Bosons mediate an attractive, finite-range interaction between fermions, leading to fermion pairing phases of different orbital symmetries. Specifically, we show that by properly tuning atomic and lattice parameters it is possible to create superfluids with $s$-, $p$-, and d-wave pairing symmetry as well as spin and charge density wave phases. These phases and their stability are analyzed within the mean-field approximation for systems of $^{40}$K-$^{87}$Rb and $^{40}$K-$^{23}$Na mixtures. For the experimentally accessible regime of parameters, superfluids with unconventional fermion pairing have transition temperature around a percent of the Fermi energy.