Realization of a flux-flow DC-transformer using high temperature superconductors

This paper reports on the first realization using high temperature supercon ducting films of the device proposed in 1965 by Giaever: the DC-DC transfor mer, which involves flux-flow vortex motion in two superimposed thin films, separated by a thin insulating layer. The device was fabricated using the ramp based multilayer technology from an YBa2Cu3O7 based SIS structure grow n by pulsed laser deposition. Transport measurements exhibiting the couplin g and decoupling phenomena between the two vortex arrays are obtained. We d iscuss the possibility of widening the working range of this device, which constitutes an important result in the effort to use high temperature super conductors for electronics.