Localization of magnon modes in a curved magnetic nanowire

TL;DR

This paper investigates how local curvature in magnetic nanowires can trap magnon modes, deriving an analytical expression for their eigenfrequencies and confirming the findings through simulations of spin wave scattering.

Contribution

It provides a general analytical formula for the eigenfrequency of localized magnon modes caused by infinitesimal curvature in magnetic nanowires.

Findings

Localized magnon modes are determined by wire curvature.

Scattering features are observed when spin waves interact with the bend.

Analytical results are confirmed by spin-lattice simulations.

Abstract

Spin waves in magnetic nanowires can be bound by a local bending of the wire. The eigenfrequency of a truly local magnon mode is determined by the curvature: a general analytical expression is established for any infinitesimally weak localized curvature of the wire. The interaction of the local mode with spin waves, propagating through the bend, results in scattering features, which is well confirmed by spin-lattice simulations.