Ju l 1 99 9 Non linear flux flow in TiN superconducting thin film

We have studied the superconducting behavior of a 100 nm Titanium Nitride (TiN) thin film in a perpendicular magnetic field. We found a zero field transition temperature of 4.6 K and a slope for the transition line in the H-T plane of −0.745 T /K. At 4.2 K, we have performed careful transport measurements by measuring both the differential resistivity and voltage as a function of a DC current. Our results are analyzed in the framework of linear and non linear flux flow behavior. In particular, we have observed an electronic instability at high vortex velocities and from its dependence with respect to the applied magnetic field, we can extract the inelastic scattering time and the diffusion length of the quasiparticles.