On the orientation of the moving flux line lattice in a superconducting film

The experimental counter-evidence is presented for Schmid and Hauger's theory which predicts the orientation of the moving flux line lattice relative to the direction of its flow. The pinning current and the current-versus-voltage characteristics of the flux flow state, together with the interference effects of the moving flux line lattice of indium films, are measured under two different experimental conditions, where either externally regulated dc voltage or current is supplied to the specimen. No difference is found between the two conditions. The theoretical arguments which predict a different orientation according to the conditions are no longer valid