PHASE-SLIP CENTERS OF SUPERCONDUCTING INDIUM BRIDGES WITH VARIABLE THICKNESS IN A MAGNETIC-FIELD

We have measured current-voltage (I-V) curves in magnetic fields H, for indium variable-thickness bridges whose strips were quasi-one-dimensional superconductors. The I-V curves take three different types depending on the H regions. One has hysteresis due to phase-slip centers. The others have no hysteresis. The critical current against H shows hysteresis owing to the surface currents induced by H. The modification of the pair-breaking time was introduced to treat the H dependence of the hysteresis of I-V curves. © 1990 Plenum Publishing Corporation.