Applied Physics Letters

Linewidth of submillimeter wave flux-flow oscillators

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

Published Jul 29, 1996• 32 citations

Abstract

A reliable technique for wide band measurements of the spectral linewidth of superconducting oscillators integrated on-chip with superconductor-insulator-superconductor (SIS) detectors has been developed. The spectral linewidth of flux-flow oscillators (FFO) based on the unidirectional and viscous flow of magnetic vortices in a long overdamped Josephson tunnel junction was measured in the frequency range 250–580 GHz, and a linewidth as low as 200 kHz was obtained at 450 GHz. Also stable frequency locking of a FFO to very high (≤60th) harmonics of an external microwave reference source has been demonstrated. The proposed technique may improve the sensitivity, frequency resolution, and stability of the fully superconducting integrated submillimeter wave receiver.

DOI: 10.1063/1.117811

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