Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors

Clem, John R. ; Smith, Stephen J. ; Sadleir, John E. ; Chervenak, James A. ; Bandler, Simon R.

PID  :  NTRS Document ID: 20100020181

学科分类：电子与电气工程

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

We have found experimentally that the critical current of a square thin-film superconducting transition-edge sensor (TES) depends exponentially upon the side length L and the square root of the temperature T, a behavior that has a natural theoretical explanation in terms of longitudinal proximity effects if the TES is regarded as a weak link between superconducting leads. As a consequence, the effective transition temperature T(sub c) of the TES is current-dependent and at fixed current scales as 1/L(sup 2). We also have found that the critical current can show clear Fraunhofer-like oscillations in an applied magnetic field, similar to those found in Josephson junctions. We have observed the longitudinal proximity effect in these devices over extraordinarily long lengths up to 290 micrometers, 1450 times the mean-free path.