Optical probing of magnons and phonons in Ni80Fe20 nanodot arrays

TL;DR

This study uses optical methods to investigate how spin waves and acoustic waves interact in Ni80Fe20 nanodot arrays, revealing the importance of lattice structure for magnetoelastic coupling and potential for energy-efficient devices.

Contribution

It demonstrates the resonant coupling of spin and acoustic waves in nanodot arrays and highlights the influence of lattice type on magnetoelastic interactions.

Findings

Resonant coupling of spin and acoustic waves observed.

Lattice type critically affects magnetoelastic interaction.

Potential for energy-efficient magnetoacoustic devices.

Abstract

Control of collective spin excitations by static or dynamic strain is an emerging phenomenon that requires in-depth understanding for design of future spin-wave-regulated devices. Here, we explore mutually interacting spin waves and acoustic wave modes in addition to few non-interactive modes through all optical excitation in ordered arrays of Ni80Fe20 nanomagnets. The acoustic wave originated from elastic deformation resonantly couple to the spin wave via magnetoelastic effect at their overlapping frequency. We demonstrate that the choice of the lattice type in which the magnetic nanodots are arranged is crucial for the observation of the magnetoelastic interaction. Therefore, the study shows that the simultaneous existence of elastic wave and spin wave offer ingeneously advantageous features to pave the way of energy-efficient magnetoacoustic devices.