An InP-Based Mid-Wave Infrared Up-Converter Utilizing Cascade Carrier Transportation

Semiconductor-based up-conversion infrared (IR) photodetectors have the advantages of pixelless imaging and being free from thermal mismatch between photodetector and read-out integrated circuit. Profited by cascade carrier transportation, cascade IR up-converters (CIUPs) provide a fresh idea to ease the contradiction between dark current and responsivity. For GaAs-based mid-wave IR CIUP, a strained InGaAs/AlGaAs material system is an essential configuration, in spite of the limitation of lattice-mismatched epitaxy. An InGaAs/InAlAs material system lattice-matched to InP substrate is a promising alternative to the strained InGaAs/AlGaAs structures. In this letter, an InP-based mid-wave IR CIUP is demonstrated with a 4.7-
$\mu \text{m}$
peak response wavelength and 1.19-
$\mu \text{m}$
peak emission wavelength. For the up-conversion system, the dark-current-limited detectivity reaches
$1.1\times 10^{11}$
Jones at 78 K and 1.3 V CIUP bias, and the background-limited infrared performance condition is achieved at 107 K with the detectivity of
$1.2\times 10^{10}$
Jones.