Bias-selectable tricolor tunneling quantum dot infrared photodetector for atmospheric windows

Abstract

A tricolor infrared detector with bias-selectable peaks based on tunneling quantum dot infrared photodetector (T-QDIP) architecture is demonstrated. Photoabsorption takes place in ${\mathrm{In}}_{0.4}{\mathrm{Ga}}_{0.6}\mathrm{As}$ quantum dots (QDs) and the excited electrons are collected by resonant tunneling across an ${\mathrm{Al}}_{0.2}{\mathrm{Ga}}_{0.8}\mathrm{As}∕{\mathrm{In}}_{0.1}{\mathrm{Ga}}_{0.9}\mathrm{As}∕{\mathrm{Al}}_{0.2}{\mathrm{Ga}}_{0.8}\mathrm{As}$ double barrier coupled to the QDs. The field dependent tunneling for excited carriers in T-QDIP is used to select the operating wavelength. This T-QDIP detector exhibits three distinct response peaks at $4.5∕4.9\pm 0.05$ , $9.5\pm 0.05$ , and $16.9\pm 0.1\mu \mathrm{m}$ up to $80\mathrm{K}$ . The peak detectivity is in the range of $(1.0–6.0)\times {10}^{12}\text{Jones}$ at $50\mathrm{K}$ . Bias polarity allows the selection of either the $9.5\mu \mathrm{m}$ or the $16.9\mu \mathrm{m}$ peak.