Quantized Josephson phase battery

Abstract

A ferromagnetic Josephson junction with a spin-flipper (magnetic impurity) sandwiched in-between acts as a phase battery that can store quantized amounts of superconducting phase difference $Φ_0$ in the ground state of the junction. Moreover, for such $Φ_0$-Josephson junction anomalous Josephson current appears at zero phase difference. We study the properties of this quantum spin-flip scattering induced anomalous Josephson current, especially its tun-ability via misorientation angle between two Ferromagnets.

11 pages (with supplementary material), 9 figures, accepted for publication in EPL (Euro Physics Letters)