Switchable spiral Josephson junction: a superconducting spin-valve proposal

Abstract

Abstract We propose a superconducting spin valve based on a Josephson junction with B20-family magnetic metal as a barrier material. Our analysis shows that the states of this element can be switched by reorienting the intrinsic non-collinear magnetization of the spiral magnet. This reorientation modifies long-range spin-triplet correlations and thereby strongly influences the critical Josephson current. Compared to superconducting spin valves proposed earlier, our device has the following advantages: (a) it contains only one barrier layer, which makes it easier to fabricate and control; (b) its ground state is stable, which prevents uncontrolled switching; (c) it is compatible with devices of low-T Josephson electronics. This device may switch between two logical states which exhibit two different values of critical current, or its positive and negative values. I.e. 0-π switch is achievable on a simple Josephson junction.