Electron-hole Superconductivity (Review)

This review is devoted to the theory of electron-hole superfluidity in bilayer systems. This is a discussion of the state in which electrons and holes from adjacent layers form bound pairs, and a nondissipative transfer of charge is caused by the motion of pairs as wholes. The occurrence of the flow of bound pairs is equivalent to the flow in conducting layers of equal in modulus but oppositely directed electric currents. Therefore, such superfluidity can be examined as a unique superconductivity that is often called counterflow superconductivity. Although this phenomenon was predicted about 40 years ago, the intensive study of the problem of electron-hole superconductivity in bilayer systems continues to date. An extensive description of theoretical representations and approaches to the problem of electron-hole superconductivity is presented in this review. Published by AIP Publishing.