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arXiv · 1909.01817

Chiral coupling of magnons in waveguides

Tao Yu·Xiang Zhang·Sanchar Sharma·Yaroslav M. Blanter·Gerrit E. W. Bauer
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Abstract

We theoretically investigate the collective excitation of multiple (sub)millimeter-sized ferromagnets mediated by waveguide photons. By the position of the magnets in the waveguide, the magnon-photon coupling can be tuned to be chiral, i.e., magnons only couple with photons propagating in one direction, leading to asymmetric transfer of angular momentum and energy between the magnets. A large imbalance in the magnon number distribution over the magnets can be achieved with a long chain of magnets, which concentrate at one edge. The chain also supports standing waves with low radiation efficiency that is inert to the chirality.

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Tao Yu, Xiang Zhang, Sanchar Sharma, Yaroslav M. Blanter, Gerrit E. W. Bauer. 2019-09-04. Chiral coupling of magnons in waveguides. https://doi.org/10.1103/physrevb.101.094414

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