Non-Hermitian physics has recently attracted much attention in optics and photonics. Less explored is non-Hermitian magnonics that provides opportunities to take advantage of the inevitable dissipation of magnons or spin waves in magnetic systems. Here we demonstrate non-Hermitian coherent coupling of two distant nanomagnets by fast spin waves with sub-50 nm wavelengths. Magnons in two nanomagnets are unidirectionally phase-locked with phase shifts controlled by magnon spin torque and spin-wave propagation. Our results are attractive for analog neuromorphic computing that requires unidirectional information transmission.
@article{arxiv.2005.10452,
title = {Non-Hermitian coherent coupling of nanomagnets by exchange spin waves},
author = {Hanchen Wang and Jilei Chen and Tao Yu and Chuanpu Liu and Chenyang Guo and Hao Jia and Song Liu and Ka Shen and Tao Liu and Jianyu Zhang and Marco A. Cabero Z and Qiuming Song and Sa Tu and Mingzhong Wu and Xiufeng Han and Ke Xia and Dapeng Yu and Gerrit E. W. Bauer and Haiming Yu},
journal= {arXiv preprint arXiv:2005.10452},
year = {2021}
}