Electron localization and interaction effects in Au/Si multilayered systems

Abstract

We have studied the temperature and magnetic field dependence of the conductivity of Au/Si multilayers with individual layer thickness 2.6 A\r{}\ensuremath{\le}${t}_{\mathrm{Au}\mathrm{\ensuremath{\le}}13}$ A\r{} and 14 A\r{}\ensuremath{\le}${t}_{\mathrm{Si}\mathrm{\ensuremath{\le}}110}$ A\r{} for Au and Si, respectively. For ${t}_{\mathrm{Au}\mathrm{\ensuremath{\gtrsim}}4}$ A\r{}, a metallic conductivity is observed. For ${t}_{\mathrm{Si}\mathrm{\ensuremath{\gtrsim}}45}$ A\r{}, the two-dimensional electron localization and interaction models account fairly well for the data, and thus allows us to determine the temperature dependence of the phase-breaking rate. For ${t}_{\mathrm{Si}\ensuremath{\lesssim}45}$ A\r{}, our results indicate the onset of coupling between the Au layers through the Si layers. A crossover to a three-dimensional behavior is observed for ${t}_{\mathrm{Si}\mathrm{\ensuremath{\approxeq}}15}$ A\r{}. .AE