| 摘要 |
The fluxon oscillators for producing electromagnetic radiation having a wavelength shorter than the shortest radio waves, but longer than the longest infrared radiation, may comprise two closely spaced superconductive ring-shaped members having a ring-shaped Josephson junction barrier therebetween capable of supporting the tunnelling of superconductive electrons across such barrier, a source of magnetic flux for initially producing at least one fluxon in the barrier, a power supply for producing an electrical biasing current between the superconductive members and across the barrier for causing movement of the fluxon along and around the ring-shaped barrier in a closed path, and a plurality of centers to produce enhanced superconductive electron current across the barrier, such centers being spaced around the ring-shaped barrier for causing cyclical variations in the velocity of the fluxon and thereby causing the radiation of electromagnetic energy at a frequency corresponding to the frequency of such cyclical variations. Such centers may comprise localized microshorts or weak links which are conductive to normal tunnelling electrons and exhibit enhanced tunnelling by superconductive electrons. Such weak links may be made of a normally conductive metal, such as copper, silver or gold. The superconductive members may be in the form of superimposed ring-shaped layers with the barrier sandwiched therebetween, or in the form of concentric inner and outer ring-shaped layers, with the barrier being disposed between the edges thereof. Such centers may also be provided by photoconductive material in the barrier, illuminated by a pattern of illumination.
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