# Controlling acoustic waves using magnetoelastic Fano resonances

## TL;DR

This paper introduces a theoretical framework for magneto-elastic devices that manipulate acoustic waves via Fano resonances, enabling energy-efficient control of wave transmission for signal processing applications.

## Contribution

It presents a novel theoretical analysis of magneto-elastic devices utilizing Fano resonances to control acoustic wave scattering, including methods to enhance coupling and mitigate losses.

## Key findings

- Resonant control of acoustic wave transmission via magnetic field tuning.
- Enhanced magnetoelastic coupling through oblique incidence geometry.
- Potential for energy-efficient acoustic signal processing devices.

## Abstract

We propose and analyze theoretically a class of energy-efficient magneto-elastic devices for analogue signal processing. The signals are carried by transverse acoustic waves while the bias magnetic field controls their scattering from a magneto-elastic slab. By tuning the bias field, one can alter the resonant frequency at which the propagating acoustic waves hybridize with the magnetic modes, and thereby control transmission and reflection coefficients of the acoustic waves. The scattering coefficients exhibit Breit-Wigner/Fano resonant behaviour akin to inelastic scattering in atomic and nuclear physics. Employing oblique incidence geometry, one can effectively enhance the strength of magnetoelastic coupling, and thus countermand the magnetic losses due to the Gilbert damping. We apply our theory to discuss potential benefits and issues in realistic systems and suggest further routes to enhance performance of the proposed devices.