Low-temperature resistance saturation in Si–δ-doped GaAs structure with Π-like gate electrode

It is observed that at temperatures below View the MathML source the resistance of gated Si–δ-doped GaAs structure in the case of carrier localization exhibits unexpected saturation instead of exponential growth as the variable-range hopping (VRH) mechanism conductivity dictates. We experimentally show that this effect is observed if gate electrode covers both the top and the sidewalls of the sample. We guess that a “metallic-like” channel, which bypasses VRH conductive channel at low temperatures appears due to side-wall gate.