Critical current density in thin superconducting TaN film structures

Abstract

The critical current density jC in thin TaN film single-bridge structures with different width from 60 nm to 8 lmhas been studied in a wide temperature range from 4.2 K up to TC=10.2 K. At T<TC, the jC(T) curves of all bridges are described by the temperature dependence of the Ginzburg–Landau de-paring critical current in a temperature range increasing with the decrease in width of the bridges. However the zero-temperature value of the critical current density jexp C (0) used as fitting parameter decreases monotonically with the decrease in width of the bridges below 1 mum.