Hydrostatic pressure studies of an asymmetrically doped resonant tunneling diode

A study has been made of the effect of hydrostatic pressure on an AlAs/GaAs/AlAs resonant tunneling diode in which the electrodes have been deliberately asymmetrically doped. In reverse bias, current is injected into the structure from a highly doped n+-GaAs electrode and in forward bias from a two-dimensional accumulation layer at the GaAs/AlAs interface. When large hydrostatic pressures are applied at 77 K, regions of negative differential resistance are induced in both bias directions. Current maxima with peak-to-valley ratios as large as 4 have been measured at 8 kbar. The intrinsic asymmetry of the structure aids in the identification of the origins of these features in terms of the X-point conduction-band minima of the device.