In NASA’s 2019 Astrophysics Biennial Technology Report “tunable-bandwidth array receivers for operation at frequencies of 1 – 5 THz,” is described as a tier 2 technology gap priority [1]. Specifically, there is a need “for LO [local oscillator], sources with output power levels ≥ 10 µW at frequencies above 2 THz,” pumping “arrays of 10 to 100 pixels.” THz Quantum Cascade Lasers are excellent candidate LOs in this frequency range because of their multi-milliwatt power levels, necessary to pump pixel arrays of superconducting hot electron bolometer mixers, as well as room temperature Schottky diode mixers. Recently, demonstrations of QCLs emission spanning 1.6 to 4.5 THz suggests the possibility of a WIdeband LO (WITLO). In this work LongWave will develop mode matching structures to provide effective anti-reflection coatings for its QLCs. This will enhance output power and wall plug efficiency of its lasers, and enable external cavity tuning. LongWave will develop specifications and a design for integration of this QCL with amplitude stabilization as well as low SWaP cryocooling necessary for future NASA missions.
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