A1 Journal article (refereed)
Dynamics of Two Ferromagnetic Insulators Coupled by Superconducting Spin Current (2022)

Ojajärvi, R., Bergeret, F. S., Silaev, M. A., & Heikkilä, T. T. (2022). Dynamics of Two Ferromagnetic Insulators Coupled by Superconducting Spin Current. Physical Review Letters, 128(16), Article 167701. https://doi.org/10.1103/PhysRevLett.128.167701

JYU authors or editors

Ojajärvi, Risto
Silaev, Mikhail
Heikkilä, Tero

Publication details

All authors or editors: Ojajärvi, Risto; Bergeret, F. S.; Silaev, M. A.; Heikkilä, Tero T.

Journal or series: Physical Review Letters

ISSN: 0031-9007

eISSN: 1079-7114

Publication year: 2022

Publication date: 20/04/2022

Volume: 128

Issue number: 16

Article number: 167701

Publisher: American Physical Society (APS)

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1103/PhysRevLett.128.167701

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/81165

Publication is parallel published: https://arxiv.org/abs/2107.09959

Abstract

A conventional superconductor sandwiched between two ferromagnets can maintain coherent equilibrium spin current. This spin supercurrent results from the rotation of odd-frequency spin correlations induced in the superconductor by the magnetic proximity effect. In the absence of intrinsic magnetization, the superconductor cannot maintain multiple rotations of the triplet component but instead provides a Josephson type weak link for the spin supercurrent. We determine the analog of the current-phase relation in various circumstances and show how it can be accessed in experiments on dynamic magnetization. In particular, concentrating on the magnetic hysteresis and the ferromagnetic resonance response, we show how the spin supercurrent affects the nonequilibrium dynamics of magnetization which depends on a competition between spin supercurrent mediated static exchange contribution and a dynamic spin pumping contribution. Depending on the outcome of this competition, a mode crossing in the system can either be an avoided crossing or mode locking.

Keywords: superconductors; superconductivity; electromagnetic fields

Fields of science: