New phenomena in coupled transport between 2D and 3D electron-gas layers

Abstract

We report, for the first time, measurements of a current-to-current coupling between 2D and 3D electron-gas (EG) layers in the AlGaAs/GaAs system, utilizing an n+ GaAs gate as the 3DEG layer. Current driven through either of the layers, which are only 30 nm apart, induces current flow in the other layer. Current-to-current transfer ratios of the order of 3×10-5 have been observed, and there is a sign reversal of the interaction at temperatures below 40 K. This and other effects can be explained by invoking Coulomb mutual scattering to couple energy and momentum between the two layers. © 1989 The American Physical Society.