Voltage jumps in current-voltage characteristics of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} superconducting films: Evidence for flux-flow instability under the influence of self-heating

We present the observation of voltage jumps at high flux-flow velocities in current-voltage characteristics of c-axis-oriented Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} superconducting thin films. The experimental results agree quantitatively with the prediction for viscous flux-flow instability including consideration of a finite heat-removal rate from the samples. We obtained a characteristic magnetic field B{sub T}, which separates the regions where the instability is dominated by nonthermal and heating mechanisms. The inelastic scattering rate 1/{tau}{sub in} and the diffusion length l{sub e} of the quasiparticles have also been extracted. {copyright} {ital 1998} {ital The American Physical Society}