Pseudo spin-valve switch based on ferromagnet/superconductor/ferromagnet trilayer microbridge

A noticeable magnetoresistive effect has been observed on ferromagnet/superconductor/ferromagnet (FSF) microbridges based on diluted ferromagnetic PdFe alloy containing as small as 1% magnetic atoms. Microstructuring of the FSF trilayers does not destroy the effect: the most pronounced curves were obtained on the smallest bridges of 6-8 um wide and 10-15 um long. Below the superconducting transition we are able to control the critical current of microbridges by switching between P and AP orientations of magnetizations of PdFe layers. The operation of FSF-bridge as a magnetic switch is demonstrated in several regimes providing significant voltage discrimination between digital states or remarkably low bit error rate.