Plasma Instabilities in Superconducting Layers

对由薄绝缘层隔开的YBCO超导层和Nb超导层组成的器件中等离子体波不稳定性的理论预测进行了实验研究。理论工作表明，当平行超导层之间的相对漂移速度较大时，可能存在放大的等离子体模，并可能因电磁辐射而损失能量。这种效应类似于双组分无碰撞等离子体的“双光束等离子体不稳定性”。这项研究旨在通过a)研究两层之间存在相对漂移速度时的电流-电压特性，以及b)在低温下使用测辐射热计探测器来探测发射的辐射，来探索这种效应。该效应在近单色长波电磁辐射发生器的设计中可能具有长期的实际应用价值。

An experimental search for theoretically predicted plasma wave instabilities in devices consisting of a superconducting layer of YBCO separated from a superconducting layer of niobium by a thin insulating layer is proposed. Theoretical work has shown that when the relative drift velocity between the parallel superconducting layers is large, an amplified plasma mode may exist, and can lose energy by electromagnetic radiation. This effect is similar to the 'two-beam plasma instability' for two- component collisionless plasmas. The research is to search for this effect by a) studying the current-voltage characteristics when a relative drift velocity exists between the two layers, and b) using bolometric detectors at low temperatures to detect the emitted radiation. The effect may have a long-term practical application in the design of generators of nearly monochromatic long-wavelength electromagnetic radiation.