Ferromagnetic resonance modulation in $d$-wave superconductor/ferromagnetic insulator bilayer systems

TL;DR

This paper theoretically studies how ferromagnetic resonance (FMR) modulation in $d$-wave superconductor/ferromagnetic insulator bilayers reveals the superconductor's nodal structure, suggesting spin pumping as a sensitive probe for unconventional superconductivity.

Contribution

It introduces a theoretical analysis of FMR modulation in $d$-wave superconductor/ferromagnetic insulator bilayers, highlighting the power-law decay and potential for high-sensitivity symmetry detection.

Findings

FMR modulation reflects $d$-wave superconductor nodes

Power-law decay in damping at low temperature and frequency

Spin pumping can probe superconductor symmetry

Abstract

We investigate ferromagnetic resonance (FMR) modulation in $d$-wave superconductor (SC)/ferromagnetic insulator (FI) bilayer systems theoretically. The modulation of the Gilbert damping in these systems reflects the existence of nodes in the $d$-wave SC and shows power-law decay characteristics within the low-temperature and low-frequency limit. Our results indicate the effectiveness of use of spin pumping as a probe technique to determine the symmetry of unconventional SCs with high sensitivity for nanoscale thin films.