Demonstration of exchange biased de Gennes spin valves

Abstract

De Gennes spin valves, consisting of a thin superconductor sandwiched between two ferromagnetic insulating layers, have been shown to exhibit nonvolatile bistable switching behavior, making them attractive devices for a variety of cryogenic electronic applications. In this work, we introduce an additional control knob by interfacing one of the ferromagnetic insulator layers with an antiferromagnet, thereby invoking the phenomenon of exchange bias. We demonstrate that such exchange biased de Gennes spin valves show field cooling direction-dependent variation in Tc, and exhibit more robust nonvolatile bistability due to antiferromagnet-induced modification of the magnetic switching behavior, including a substantial coercivity enhancement, significantly reducing the sensitivity of their switching behavior to small magnetic field fluctuations.