Dominant photogenerated valley current in a double-barrier resonant-tunneling diode

Dominant photogenerated valley current has been observed in an optically-excited InGaAs/AlAs double-barrier resonant-tunneling diode. The photogenerated valley current in the resonant-tunneling diode varies with the optical power level. Under intense illumination, the photogenerated valley current increases to such a high level that it becomes dominant over the peak current. As a consequence, the negative differential resistance of the device is removed. The observed photogenerated valley current is described by photogenerating electron-hole pairs in the depletion region adjacent to the double-barrier structure. Transient behavior of the photogenerated carriers is also studied. The observed dominant photogenerated valley current may have useful applications.