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## Superfluid drag between excitonic polaritons and superconducting electron gas

The Andreev-Bashkin effect, or superfluid drag, is predicted in a system of Bose-condensed excitonic polaritons in optical microcavity coupled by electron-exciton interaction with a superconducting layer. Two possible setups with spatially indirect dipole excitons or direct excitons are considered. The drag density characterizing a magnitude of this effect is found by many-body calculations with taking into account dynamical screening of electron-exciton interaction. For the superconducting electronic layer, we assume the recently proposed polaritonic mechanism of Cooper pairing, although the preexisting thin-film superconductor should also demonstrate the effect. According to our calculations, the drag density can reach considerable values in realistic conditions, with excitonic and electronic layers made from GaAs-based quantum wells or two-dimensional transition metal dichalcogenides. The predicted nondissipative drag could be strong enough to be observable as induction of a supercurrent in the electronic layer by a flow of polariton Bose condensate.