Characterization of the Performance of a Quasi-Optical NbN Superconducting HEB Mixer

• Published in: IEEE transactions on applied superconductivity Vol. 17; no. 2; pp. 395 - 398
• Main Authors: Jiang, L., Antipov, S.V., Voronov, B.M., Gol'tsman, G.N., Zhang, W., Li, N., Lin, Z.H., Yao, Q.J., Miao, W., Shi, S.C., Svechnikov, S.I., Vakhtomin, Y.B.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2007; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antennas; Bolometers; Devices; Electrons; Frequency; Intermediate frequency; LO power requirement; Local oscillators; Mixers; Noise measurement; Noise temperature; Oscillators; Power generation; Stability; Superconducting device noise; Superconducting films; superconducting hot-electron bolometer (HEB) mixer; Superconductivity; Temperature; transmission coefficient
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2007.897875

In this paper we focus mainly on the investigation of the performance of a quasi-optical (planar log-spiral antenna) phonon-cooled NbN superconducting hot electron bolometer (HEB) mixer, which is cryogenically cooled by a close-cycled 4-K cryocooler, at 500 and 850 GHz frequency bands. The mixer's noise performance, stability of IF output power, and local oscillator (LO) power requirement are characterized for three NbN superconducting HEB devices of different sizes. The transmission characteristics of Mylar and Zitex films with incidence waves of an elliptical polarization are also examined by measuring the mixer's noise temperature. The lowest receiver noise temperatures (with no corrections) of 750 and 1100 K are measured at 500 and 850 GHz, respectively. Experimental results also demonstrate that the bigger the HEB device is, the higher the stability of IF output power becomes.