Non-linear off-state characteristics of ovshinsky switching devices

Abstract

The non-linear conductivity of the OFF state of a chalcogenide glass switch is explained by a model of phonon-assisted Zener tunneling. A phonon instantaneously populates an unstable barrier state between dangling bond states, and the electron coherently tunnels across the small remaining mobility gap. The energy levels are themselves field-dependent. A second-quantized effective tunnelling Hamiltonian and simple golden-rule argument are used. We obtain the experimentally fitted field and temperature dependence and parameter magnitudes.