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

A 30% bandwidth tunerless SIS mixer of quantum-limited sensitivity for Herschel / HIFI Band 1

Morvan C. Salez, Y. Delorme, I. Péron, B. Lecomte, Frédéric Dauplay, Faouzi M. Boussaha, J. Spatazza, A. Féret, Jean-Michel Krieg, Karl-Friedrich Schuster

Published Feb 1, 2003• 8 citations

Publisher

Abstract

We report on the status of the development of a 30% bandwidth tunerless SIS double-sideband mixer for the “Band 1” (480 GHz-630 GHz) channel of the heterodyne instrument (HIFI) of ESA’s Herschel Space Observatory, scheduled for launch in 2007. After exposing the main features of our mixer design, we present the performance achieved by the demonstration mixer, measured via Fourier Transform Spectroscopy and heterodyne Y factor calibrations. We infer from a preliminary mixer analysis that the mixer has very low, quantum-limited noise and low conversion loss. We also report on some pre-qualification tests, as we currently start to manufacture the qualification models and design the last iteration of masks for SIS junction production.

DOI: 10.1117/12.459365

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