Anomalous Andreev interferometer: Study of an anomalous Josephson junction coupled to a normal wire

Abstract

Josephson junctions (JJs), where both time-reversal and inversion symmetry are broken, exhibit a phase shift φ0 in their current-phase relation. This allows for an anomalous supercurrent to flow in the junction even in the absence of a phase bias between the superconductors. We show that a finite phase shift also manifests in the so-called Andreev interferometers - a device that consists of a mesoscopic conductor coupled to the φ0 junction. Due to the proximity effect, the resistance of this conductor is phase sensitive - it oscillates by varying the phase of the JJ. As a result, the quasiparticle current Iqp flowing through the conductor has an anomalous component, which exists only at finite φ0. Thus, the Andreev interferometry could be used to probe the φ0 effect. We consider two realizations of the φ0 junction and calculate Iqp in the interferometer: a superconducting structure with spin-orbit coupling and a system of spin-split superconductors with spin-polarized tunneling barriers.