Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Far-field beam-pattern of a twin-slot HEB mixer at 600GHz

Kangmin Zhou, Y. Delorme, Roland Lefèvre, Frédéric Dauplay, A. Féret, T. Vacelet, Zheng Lou, Sheng‐Cai Shi

Published Nov 10, 2014• 0 citations

Abstract

In this paper, we report on the measured and simulated far-field beam-patterns of a quasi-optical NbN superconducting hot electron bolometer (HEB) mixer at 600GHz. This superconducting HEB mixer consists of an extended hemispherical lens with a diameter of 12.7mm and an extension length of 2.45mm, a twin-slot planar antenna (two slots measuring 148.5μm × 10.4μm with a separation of 78.98μm) and a 5.5-nm thick NbN thin-film micro-bridge with an area of 2μm × 0.2μm . The far-field beam pattern of this mixer is measured by a direct-detection technique with a dynamic range of nearly 25dB, showing an FWHM beam angle of 2.7° and -18dB level of the first side-lobe. The measured beam of the quasi-optical mixer is nearly collimated and has good Gaussian beam efficiency. In addition, the far-field beam-pattern is measured at different DC bias voltages of the superconducting HEB mixer and at different bath temperatures. The measured results are compared with the ones simulated by two different methods. Detailed measurement and simulation results will be presented.

DOI: 10.1117/12.2070936

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