Description: In this Phase II-E work, LongWave proposes to demonstrate a 4.7 THz QCL in a compact cryocooler as a local oscillator for a Schottky Diode mixer. QCL power and RF power will be combined using a Martin Puplett interferometer. This design is advantageous because it maximizes the use of QCL power compared with the beamsplitter, which typically discards >90% of QCL power.

Benefits: Potential NASA applications include use as a local oscillator for Origins Space Telescope, GUSTO (Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory), ASTHROS (Astrophysics Stratospheric Telescope for High Spectral Resolution Observations at Submillimeter-wavelengths), and instruments such as SSOLVE (Submillimeter Solar Observation Lunar Volatiles Experiment).

Initial applications are research markets for low-pressure gas spectroscopy. The narrow line width and the ability to provide real-time frequency information of THz radiation also have great appeal. For industrial applications, the use of high reliability, compact Stirling coolers with integrated frequency and amplitude stabilization would increase the usability of these devices.