Igor Blinov, UT-Austin

"Electron-hole collective states in a double bilayer graphene and their contribution to the tunneling current"

Abstract: Recent advances in the experimental technique allowed exploring 2D materials in a wide range of external parameters (voltage difference, fillings, etc). One of the possible goals of such exploration is to find new collective states present in a system. Exciton condensate is one of such states, so far not conclusively observed in systems without magnetic field. Such condensates can be formed out of interlayer and intralayer excitons (bound states of a hole and an electron). One of the hallmarks of the exciton condensate of the first type (hole and an electron resides in different layers) is a sharp increase of tunneling current. I will show that the increase of the tunneling current due to the many-body effects can occur not only at the point of condensation and discuss the applicability of the theory.