Sub-monolayer quantum dot quantum cascade mid-infrared photodetector

Abstract

In this work, we demonstrate a sub-monolayer quantum dot quantum cascade photodetector grown on GaAs for photovoltaic mid-infrared photo-detection. The detector shows a normal-incident peak responsivity of 1.90 mA/W at the wavelength of 6.05 μm and a resistance-area product of 1.54 × 108 Ω cm2 at 77 K. The corresponding specific detectivity is 3.22 × 1011 cm·Hz1/2/W.