High-Response i-InAs/n-GaAs Quantum-Dot Infrared Photodetector with No Current Blocking Barrier

Abstract

We report a high-response normal-incidence infrared photodetector based on the bound-to-continuum transition fabricated on the self-assembled i-InAs/n-GaAs quantum-dot (QD) heterostructure doped in GaAs barrier with no current blocking barrier. The photoresponse characteristics have been confirmed by distinct methods using a SiC globar source and a blackbody radiation source. From the blackbody system, the responsivity of 1750 mA/W at a peak wavelength of ∼4.7 µm (21 K) has been achieved, which is much higher than that reported on the n-InAs/i-GaAs QD-based infrared photodetectors doped in QDs with additional barrier.