GUSTO (Gal/Xgal U/LDB Spectroscopic/Stratospheric Terahertz Observatory ) as a balloon borne observatory has been selected by NASA for the first time as a space mission targeted to be launched in 2021 from McMurdo, Antarctica. It is a proposed ~ 0.85 meter telescope with 8-pixel cryogenic heterodyne receiver arrays at 1.4, and 1.9, and 4.7 THz, respectively. A balloon-borne observatory to explore the far-infrared [OI], [CII] and [NII] lines in the Milky Way and a nearby companion galaxy. Terahertz heterodyne array receivers will provide the spectral and spatial resolution needed to untangle the complexities of the interstellar medium, probing all phases of its life cycle, from the formation of molecular clouds, through star birth and evolution, to the formation of gas clouds and the re-initiation of the cycle.

Gao’s team provides state-of-the-art superconducting hot electron bolometer (HEB) mixers for all three frequency bands of GUSTO, which is the key in its realization. The team also contribute to the local oscillator (LO) development of the 4.7 THz receiver of GUSTO by providing a 1 to 8 LO beam multiplexer based on a phase grating.

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Objective

• Providing the key detector technology for the 1.4, 1.9 , and 4.7 THz cameras of GUSTO, which are based on NbN HEB mixers, making use of nanotechnology and superconductivity.
• Providing LO multiplexing technology to split the beam of a 4.7 THz quantum cascade laser (QCL) into 8 for accommodating the mixer array based on a phase grating.

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Impact

Key contribution to GUSTO and the science it will provide about the formation process and the life-cycle of stars in the interstellar medium of our galaxy and beyond.

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