Conductance quantization above 30 K in GaAlAs shallow-etched quantum point contacts smoothly joined to the background 2DEG

Researchers observed quantized conductance in shallow-etched GaAs/GaAlAs quantum point contacts at temperatures up to 36 K. The temperature dependence of the quantized conductance allows the estimation of ID subband separations. These were up to 20 me V which is the highest value ever reported of lateral QPC constrictions in GaAs/GaAlAs heterostructures. The quantum point contacts also had very clean conductance quantization at the lowest temperatures.