Spin and Charge Pumping by Ferromagnetic-Superconductor Order Parameters

TL;DR

This paper investigates how adiabatic changes in ferromagnetic-superconductor order parameters can pump spin and charge currents into normal metals, revealing the symmetry of the superconducting pairing and impacting ferromagnetic-resonance experiments.

Contribution

It introduces a mechanism for spin and charge pumping via order parameter dynamics, linking superconducting symmetry to observable transport phenomena.

Findings

Charge and spin currents are pumped by order parameter changes.

Pumping reveals the symmetry of the superconducting order parameter.

Implications for ferromagnetic-resonance experiments are discussed.

Abstract

We study transport in ferromagnetic-superconductor/normal-metal systems. It is shown that charge and spin currents are pumped from ferromagnetic superconductors into adjacent normal metals by adiabatic changes in the order parameters induced by external electromagnetic fields. Spin and charge pumping identify the symmetry of the superconducting order parameter, e.g., singlet pairing or triplet pairing with opposite or equal spin pairing. Consequences for ferromagnetic-resonance experiments are discussed.