Designed spin-texture-lattice to control anisotropic magnon transport in antiferromagnets

TL;DR

This paper demonstrates how engineered spin-texture-lattice interactions can control anisotropic magnon transport in antiferromagnetic materials, advancing the development of reconfigurable magnonic devices for low-energy computing.

Contribution

It introduces a method to manipulate magnon transport anisotropy in antiferromagnets using spin-texture-lattice engineering, supported by multiscale theory and simulations.

Findings

Discovered anisotropic spin transport in a 1D magnonic crystal

Identified population imbalance and anisotropic scattering as causes

Proposed pathway for electrically-reconfigurable magnonic devices

Abstract

Spin waves in magnetic materials are promising information carriers for future computing technologies due to their ultra-low energy dissipation and long coherence length. Antiferromagnets are strong candidate materials due, in part, to their stability to external fields and larger group velocities. Multiferroic aniferromagnets, such as BiFeO$_3$ (BFO), have an additional degree of freedom stemming from magnetoelectric coupling, allowing for control of the magnetic structure, and thus spin waves, with electric field. Unfortunately, spin-wave propagation in BFO is not well understood due to the complexity of the magnetic structure. In this work, we explore long-range spin transport within an epitaxially engineered, electrically tunable, one-dimensional (1D) magnonic crystal. We discover a striking anisotropy in the spin transport parallel and perpendicular to the 1D crystal axis. Multiscale theory and simulation suggests that this preferential magnon conduction emerges from a combination of a population imbalance in its dispersion, as well as anisotropic structural scattering. This work provides a pathway to electrically-reconfigurable magnonic crystals in antiferromagnets.