Superconducting properties of TaN and VN films

Thin superconducting TaN and VN films produced by reactive cathode sputtering have been investigated. Superconducting-phase-transition smearing in applied field seems to be due to spatial fluctuations of the electron diffusion coefficient as well as dimensional crossover of dynamical superconducting order parameter fluctuations. Flux pinning occurs at grain boundaries by electron scattering mechanism. Transition to a dissipative state is induced by flux line separation from the pins but not by flux line lattice plastic shear.<
>