Influence of disorder on electron-hole pairing in graphene bilayer

We consider disorder effect on electron-hole pairing in the system of two graphene monolayers separated by dielectric barrier. The influence of charged impurities on temperature of phase transition is studied. In spite of large values of mobility of charge carriers in graphene disorder can considerably reduce temperature of electron-hole condensation in weak-coupling regime. The quantum hydrodynamics of the system is considered and phase stiffness of electron-hole condensate and temperature of Berezinskii-Kosterlitz-Thouless transition to the superfluid state are calculated.