I. Microwave Impedance of Superconducting Weak Links. I. Effects of Nonequilibrium QuasiParticle Distributions in Superconducting Weak Links.
Abstract
Nonequilibrium properties of proximity coupled superconducting weak links are studied. The impedance of a currentbiased weak link was calculated analytically on the basis of several different theoretical models for the supercurrent and the quasiparticle current, and the results were compared with experimental measurements. A very small tunnel junction was used to inject quasiparticles directly into the center of a proximity effect weak link. It was found that the critical current of the weak link was, over a wide range of experimental conditions, proportional to (alpha square root of P), where P is the injection power and alpha is a constant. The final experiment consisted of using a small tunnel junction as a probe of the nonequilibrium quasiparticle chemical potential inside a proximity effect weak link. The nonequilibrium value of potential was produced by simultaneously passing a dc bias current and a microwave current through the weak link. For most values of microwave current measured value of the quasiparticle chemical potential was proportional to the dc supercurrent carried by the weak link.
 Publication:

Ph.D. Thesis
 Pub Date:
 May 1977
 Bibcode:
 1977PhDT.........9F
 Keywords:

 Physics: Condensed Matter;
 Electrical Impedance;
 Linkages;
 Microwave Coupling;
 Superconductors;
 Current Distribution;
 Electric Current;
 Electric Potential;
 Electron Tunneling;
 Mathematical Models;
 SolidState Physics