Rectifying Single GaAsSb Nanowire Devices Based onSelf-Induced Compositional Gradients.

Device configurations that enablea unidirectional propagation of carriers in a semiconductor are fundamentalcomponents for electronic and optoelectronic applications. To realizesuch devices, however, it is generally required to have complex processesto make p–n or Schottky junctions. Here we report on a unidirectionalpropagation effect due to a self-induced compositional variation inGaAsSb nanowires (NWs). The individual GaAsSb NWs exhibit a highlyreproducible rectifying behavior, where the rectifying direction isdetermined by the NW growth direction. Combining the results fromconfocal micro-Raman spectroscopy, electron microscopy, and electricalmeasurements, the origin of the rectifying behavior is found to beassociated with a self-induced variation of the Sb and the carrierconcentrations in the NW. To demonstrate the usefulness of these GaAsSbNWs for device applications, NW-based photodetectors and logic circuitshave been made. [ABSTRACT FROM AUTHOR]