title: Frictionless flow in a binary polariton superfluid.
abstract: We study the properties of a binary microcavity polariton superfluid coherently injected by two lasers at different momenta and energies. The crossover from the supersonic to the subsonic regime, where motion is frictionless, is described by evaluating the linear response of the system to a weak defect potential. We show that the coupling between the two components requires that either both components flow without friction or both scatter against the defect, though scattering can be small when the two fluids are weakly coupled. By analyzing the drag force exerted on a defect, we give a recipe to experimentally address the crossover from the supersonic to the subsonic regime.
authors.affiliation: Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, Spain. emiliano.cancellieri@uam.es
authors.forename: E
authors.initials: E
authors.lastname: Cancellieri
authors.forename: F M
authors.initials: FM
authors.lastname: Marchetti
authors.forename: M H
authors.initials: MH
authors.lastname: Szymańska
authors.forename: D
authors.initials: D
authors.lastname: Sanvitto
authors.forename: C
authors.initials: C
authors.lastname: Tejedor