Anomalous and highly efficient InAs nanowire phototransistors based on majority carrier transport at room temperature

Core/shell-like n-type InAs nanowire phototransistors based on majority-carrier-dominated photodetection are investigated. Under optical illumination, electrons generated from the core are excited into the self-assembled near-surface photogating layer, forming a built-in electric field to significantly regulate the core conductance. Anomalous high photoconductive gain and fast response time are obtained at room temperature.