Spin-Wave Fiber

TL;DR

This paper introduces a novel spin wave fiber using magnetic domain walls that enables long-distance spin wave transmission through total internal reflection, inspired by optical fibers, advancing magnonic information technologies.

Contribution

It demonstrates a new magnetic domain structure-based spin wave fiber leveraging Dzyaloshinskii-Moriya interaction for efficient magnonic communication.

Findings

Spin waves follow a generalized Snell's law at magnetic domain walls.

Total reflection of spin waves occurs at domain walls beyond a critical incident angle.

The spin wave fiber can transmit signals over long distances via total internal reflection.

Abstract

Spin waves are collective excitations propagating in the magnetic medium with ordered magnetizations. Magnonics, utilizing the spin wave (magnon) as information carrier, is a promising candidate for low-dissipation computation and communication technologies. We discover that, due to the Dzyaloshinskii-Moriya interaction, the scattering behavior of spin wave at a magnetic domain wall follows a generalized Snell's law, where two magnetic domains work as two different mediums. Similar to optical total reflection that occurs at the water-air interfaces, spin waves may experience total reflection at magnetic domain walls when their incident angle larger than a critical value. We design a spin wave fiber using a magnetic domain structure with two domain walls, and demonstrate that such a spin wave fiber can transmit spin waves over long distance by total internal reflections, in analogy to an optical fiber. Our design of spin wave fiber opens up new possibilities in pure magnetic information processing.