Spin waves along the edge states

TL;DR

This paper investigates edge and bulk spin wave propagation in triangular Permalloy dots, revealing edge channels for effective one-dimensional spin waves in the Buckle state and two-dimensional behavior in the Y state, with implications for spintronic devices.

Contribution

It demonstrates the existence of edge channels for spin waves in triangular dots and analyzes their robustness against geometric variations and interactions, advancing spin wave control for spintronics.

Findings

Edge channels enable effective spin wave propagation in Buckle state.

Spin waves in Y state exhibit mainly two-dimensional character.

Edge spin waves are weakly affected by aspect ratio variations and dipolar interactions.

Abstract

Spin waves have been studied experimentally and by simulations in 1000 nm side equilateral triangular Permalloy dots in the Buckle state (B, with in-plane field along the triangle base) and the Y state (Y, with in-plane field perpendicular to the base). The excess of exchange energy at the triangles edges creates channels that allow effective spin wave propagation along the edges inthe B state. These quasi one-dimensional spin waves emitted by the vertex magnetic charges gradually transform from propagating to standing due to interference and(as pointed out by simulations) areweakly affected by smallvariations of the aspect ratio(from equilateral to isosceles dots) or by interdot dipolar interaction present in our dot arrays. Spin waves excited in the Y state have mainly a two-dimensional character.Propagation of the spin waves along the edge states in triangular dots opens possibilities for creation of new and versatile spintronic devices.