Superfluid Bose-Fermi mixture with spin-orbit coupling

We investigate a fermionic superfluid with Raman-induced spin-orbit coupling immersed in a Bose-Einstein condensate. By minimizing the total free energy, we find that, with moderate repulsive interspecies interaction, a phase separation occurs where the otherwise nontopological uniform phase is divided into two parts: a purely fermionic one and a Bose-Fermi mix characterized by nontrivial topology with the winding number W = 1. We verify that Majorana zero modes emerge at the phase interfaces by numerical simulations of the coupled Bogoliubov-de Gennes and Gross-Pitaevskii equations in real space. The tunability of the phase interfaces enables a direct manipulation of the predicted Majorana zero modes.