Flux flow resistivity in single crystal YBa2Cu3O7−δ

Abstract AC magnetoresistance measurements were performed on twinned single crystals of YBa 2 Cu 3 O 7−δ to study the effect of dissipative flux flow motion due to Lorentz force. We report the first direct observation of Lorentz force induced flux flow resistivity in high- T c superconductors which varies as sin 2 (θ) with respect to transport current-magnetic field orientation. However, the intrinsic broadening of the resistive transition in magnetic field exists even in the absence of Lorentz force and hence cannot be explained by flux flow dissipative resistivity.