19μm quantum cascade infrared photodetectors

摘要

Two InP based InGaAs/InAlAs photovoltaic quantum cascade detectors operating at peak wavelengths of 18 μm and 19 μm using different electronic transport mechanisms are reported. A longitudinal optical phonon extraction stair combined with energy mini-steps are employed for electron transport, which suppresses the leakage current and results in high device resistance. Altogether, this quantum design leads to 15 K peak responsivity of 2.34 mA/W and Johnson noise limited detectivity of 1 × 10~(11) Jones at 18 μm.