Perspective on Non-Hermitian Elastodynamics

TL;DR

This paper reviews recent advances in non-Hermitian elastodynamics, highlighting how concepts from non-Hermitian quantum mechanics are used to control mechanical waves and discussing future research directions.

Contribution

It provides a perspective on the unique challenges and developments in applying non-Hermitian physics to elastodynamics, contrasting it with optics and acoustics.

Findings

Non-Hermitian elastodynamics enables novel wave control phenomena.

Analogies with quantum mechanics reveal unconventional wave behaviors.

Future directions include topological phases and symmetry breaking in materials.

Abstract

The manipulation of mechanical waves is a long-standing challenge for scientists and engineers, as numerous devices require their control. The current forefront of research in the control of classical waves has emerged from a seemingly unrelated field, namely, non-Hermitian quantum mechanics. By drawing analogies between this theory and those of classical systems, researchers have discovered phenomena that defy conventional intuition and have exploited them to control light, sound, and elastic waves. Here, we provide a brief perspective on recent developments, challenges and intricacies that distinguish non-Hermitian elastodynamics from optics and acoustics. We close this perspective with an outlook on potential directions such as topological phases in non-Hermitian elastodynamics and broken Hermitian symmetry in materials with electromomentum couplings.