IEEE Transactions on Applied Superconductivity

Linewidth of frequency locked flux flow oscillators for sub-mm wave receivers

V. P. Koshelets, S. V. Shitov, А. В. Щукин, Lyudmila V. Filippenko, J. Mygind

Published Jun 1, 1997• 8 citations

Abstract

Presently Flux Flow Oscillators (FFOs) are being developed for integration with superconductor-insulator-superconductor (SIS) mixers intended for submillimeter wave integrated receivers. Here we report on a detailed study of the dc and microwave properties of Nb-AlO/sub x/-Nb FFOs. A model based on the Josephson self-pumping effect is proposed for explanation of the experimentally measured dc I-V curves (IVC). Extensive measurements of the spectral linewidth of the radiation emitted from a FFO have been performed up to 600 GHz using a new reliable technique based on harmonic mixing. The results are compared to recent theoretical predictions.

DOI: 10.1109/77.621904

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