Switchable Spiral Josephson junction: A superconducting spin-valve proposal

We propose a superconducting spin valve based on a Josephson junction with B20-family magnetic metal as 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 influences strongly the critical Josephson current. Compared to superconducting spin valves proposed earlier, our device has the following advantages: (i) it contains only one barrier layer, which makes it easier to fabricate and control; (ii) its ground state is stable, which prevents uncontrolled switching; (iii) 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 value. I.e. 0-π switch is achievable on one simple Josephson junction.