Evidence for 870 GHz phonon emission from superconducting Al tunnel diodes through resonant scattering by oxygen in silicon

Abstract

Thin-film aluminum superconducting tunnel junctions can be used to generate phonons up to 10 12 Hz. This is substantiated by the observation of the 29-cm -1 absorption line of O 16 impurities in silicon, so far only known from infrared spectra.