We demonstrate strong magnon-photon coupling of a thin-film permalloy device fabricated on a coplanar superconducting resonator. A coupling strength of 0.152 GHz and a cooperativity of 68 are found for a 30-nm-thick permalloy stripe. The coupling strength is tunable by rotating the biasing magnetic field or changing the volume of permalloy. We also observe an enhancement of magnon-photon coupling in the nonlinear regime of the superconducting resonator, which is mediated by the nucleation of dynamic flux vortices. Our results demonstrate a critical step towards future integrated hybrid systems for quantum magnonics and on-chip coherent information transfer.
@article{arxiv.1902.09715,
title = {Strong magnon-photon coupling in ferromagnet-superconducting resonator thin-film devices},
author = {Yi Li and Tomas Polakovic and Yong-Lei Wang and Jing Xu and Sergi Lendinez and Zhizhi Zhang and Junjia Ding and Trupti Khaire and Hilal Saglam and Ralu Divan and John Pearson and Wai-Kwong Kwok and Zhili Xiao and Valentine Novosad and Axel Hoffmann and Wei Zhang},
journal= {arXiv preprint arXiv:1902.09715},
year = {2019}
}