Interaction and filling-induced quantum anomalous Hall effect in ultra-cold neutral Bose-Fermi mixture on hexagonal lattice

TL;DR

This paper predicts the realization of the quantum anomalous Hall effect in ultra-cold Bose-Fermi mixtures on a hexagonal lattice by forming composite fermions through strong interactions, with potential experimental signatures.

Contribution

It introduces a novel mechanism for realizing the quantum anomalous Hall effect using composite fermions in ultra-cold Bose-Fermi mixtures on a hexagonal lattice.

Findings

Composite fermions can induce quantum anomalous Hall effect.

Tuning interactions or filling factors can realize the effect.

Experimental signatures are discussed.

Abstract

We investigate the quantum anomalous Hall effect in a mixture of ultra-cold neutral bosons and fermions held on a hexagonal optical lattice. In the strong atom-atom interaction limit, composite fermions composed of one fermion with bosons or bosonic holes in the mixture are formed. Such composite fermions have already been generated successfully in experiment [Nat. Phys. {\bf 7}, 642 (2011)]. Here we predict that this kind of composite fermions may provide a realization of the quantum anomalous Hall effect by tuning the atom-atom interaction or the filling of the bosons in the mixture. We also discuss the corresponding experimental signatures of the quantum anomalous Hall effect in the Bose-Fermi mixture on hexagonal optical lattice.