Quasi-one-dimensional ballistic electron transport in in-plane-gated channels at liquid nitrogen temperature

Abstract In-plane-gated quantum point contacts were fabricated in a pseudomorphic GaAs/InGaAs/AlGaAs heterostructure by focused ion beam implantation of 100 keV Ga + ions. We see an intricate conductance quantization structure at 4.2 K. As the temperature is increased, the quantization becomes less pronounced but clear remnants are observed even at liquid nitrogen temperature and above.