Terahertz detection with tunneling quantum dot intersublevel photodetector

Abstract

The characteristics of a tunnel quantum dot intersublevel photodetector, designed for the absorption of terahertz radiation, are described. The absorption region consists of self-organized In0.6Al0.4As∕GaAs quantum dots with tailored electronic properties. Devices exhibit spectral response from 20to75μm (∼4THz) with peak at ∼50μm. The peak responsivity and specific detectivity of the device are 0.45A∕W and 108cmHz1∕2∕W, respectively, at 4.6K for an applied bias of 1V. Response to terahertz radiation is observed up to 150K.