INTERACTION BETWEEN MOVING FLUX LINES AND A 2-DIMENSIONAL ELECTRON-GAS

A novel method is presented to study the dynamics of vortices in superconducting films at fields close to the upper critical magnetic field. It is shown that moving flux lines in the gate of a superconductor-oxide-semiconductor field-effect transistor are magnetically coupled to a two-dimensional electron gas, leading to an induced voltage. The major part of this voltage is proportional to the magnetoresistance, which is varied by changing the Landau-level filling. A second part is independent of the electron density and is tentatively attributed to the Hall component of the resistivity tensor.