Superconducting Interfaces Between Insulating Oxides

摘要

At interfaces between complex oxides, electronic systems with unusual electronic properties can be generated. We report on superconductivity in the electron gas formed at the interface between two insulating dielectric perovskite oxides, LaAlO_3 and SrTiO_3, The behavior of the electron gas is that of a two-dimensional superconductor, confined to a thin sheet at the interface. The superconducting transition temperature of ≌ 200 millikelvin provides a strict upper limit to the thickness of the superconducting layer of ≌ 10 nanometers.