Andreev current induced by ferromagnetic resonance

TL;DR

This paper investigates how ferromagnetic resonance in a ferromagnetic-superconductor junction induces a direct current through a metallic dot, revealing a rectification effect of ac spin currents in the subgap regime.

Contribution

It demonstrates the generation of dc current by magnetization precession without bias voltage, highlighting the role of interface rectification and the impact of superconducting coupling.

Findings

Precession induces dc current in the absence of bias.

Strong coupling to superconductor enhances the effect.

Rectification occurs despite no spin current in the superconductor.

Abstract

We study charge transport through a metallic dot coupled to a superconducting and a ferromagnetic lead with a precessing magnetization due to ferromagnetic resonance. Using the quasiclassical theory, we find that the magnetization precession induces a dc current in the subgap regime even in the absence of a bias voltage. This effect is due to the rectification of the ac spin currents at the interface with the ferromagnet; it exists in the absence of spin current in the superconductor. When the dot is strongly coupled to the superconductor, we find a strong enhancement in a wide range of parameters as compared to the induced current in the normal state.