Superfluidity of dipole excitons in the presence of band gaps in two-layer graphene

We propose to observe superfluidity of quasi-two-dimensional dipole excitons in double-layer graphene in the presence of band gaps. The energy spectrum of the collective excitations, the sound spectrum, and the effective exciton mass are functions of the energy gaps, density, and interlayer separation. The superfluid density nₛ and temperature of the Kosterlitz-Thouless phase transition Tc are decreasing functions of the energy gaps.