Electron Tunneling from an Ultrathin Quantum Well in Constant and Alternating Electric Fields

The change of electron tunneling probability with time after instantaneous application of an electric field is calculated for a one-dimensional ultrathin quantum well (QW). The electronic wave function bound to such QW is characterized by relatively large exponential tails on both sides of the QW. By solving the time dependent Schrodinger equation exactly, it is demonstrated that the tunneling rate is substantially larger than that predicted by standard approximations. This property may appear useful in constructing new ultrahigh-speed solid state devices based on isolated QWs. [Russian Text Ignored].