Nonlinear Mechanical Roton

Abstract

Abstract The roton-like dispersions support the “return flow” of acoustic waves; such phenomena were only observed in quantum systems. In this paper, we aim to investigate the nonlinear roton-like dispersion in a mechanical metamaterial with both nonlinear chains and nonlinear resonators with nonlocal connection; both theoretical and numerical methods are used to analyze the system, and some new phenomena such as amplitude-dependent roton-like behaviors are observed. This work opens a new way for designing an extremely low-frequency vibration isolator with a stable configuration.