1211.1859 (K. V. Germash et al.)

Electron-hole pairing in topological insulator heterostructures in the
quantum Hall state    [PDF]

K. V. Germash, D. V. Fil

A thin film of topological insulator (TI) on a dielectric substrate and a structure "bulk TI - dielectric film - bulk TI" are considered as natural double-well heterostructures suitable for a realization of counterflow superconductivity. The effect is connected with pairing of electrons and holes belonging to different surfaces of TI and transition of bound electron-hole pairs into superfluid state. The case of TI heterostructures subjected by a strong perpendicular magnetic field is considered. It is shown that such systems are characterized by two critical temperatures - a mean-field temperature of pairing and a much smaller temperature of superfluid transition. The dependence of critical temperatures on magnetic field is computed. The advantages of TI based structures in comparison with GaAs heterostructures as well as graphene based heterostructures are discussed.

View original: http://arxiv.org/abs/1211.1859