Dissipation in the superconducting mixed state in the presence of a small oscillatory magnetic-field component

Abstract

We have studied the electric resistivity in superconducting amorphous ${\mathrm{Mo}}_{3}$Si films in a perpendicular magnetic field ${\mathrm{B}}_{0}$+${\mathrm{B}}_{1}$ sin \ensuremath{\omega}t with ${\mathrm{B}}_{1}$\ensuremath{\ll}${\mathrm{B}}_{0}$. For ${\mathrm{B}}_{1}$=0 a resistive voltage only appeared due to flux creep above the critical current ${\mathrm{I}}_{\mathrm{c}}$. For ${\mathrm{B}}_{1}$>0 we observed perfectly Ohmic behavior at currents I\ensuremath{\ll}${\mathrm{I}}_{\mathrm{c}}$n(${\mathrm{B}}_{1}$=0), with the resistivity increasing proportional to \ensuremath{\omega} and ${\mathrm{B}}_{1}$. We present a simplified model discussion explaining our results in terms of the magnetic flux transferred across the sample during each cycle of the oscillatory magnetic field because of the electric transport current.