Mesoscopic chaos mediated by Drude electron-hole plasma in silicon optomechanical oscillators

TL;DR

This paper demonstrates deterministic chaos in silicon-based optomechanical oscillators driven by nonlinear Drude electron-hole plasma effects, providing insights into mesoscopic chaos with potential for scalable CMOS-compatible applications.

Contribution

It introduces a novel silicon optomechanical system exhibiting chaos through two-photon absorption-induced plasma nonlinearities, with detailed dynamical characterization.

Findings

Chaotic oscillations achieved at 60 fJ intracavity energy

Correlation dimension of 1.67 and Lyapunov exponent of 2.94 measured

Maps reveal bifurcations, subharmonics, and chaos transition routes

Abstract

Chaos has revolutionized the field of nonlinear science and stimulated foundational studies from neural networks, extreme event statistics, to physics of electron transport. Recent studies in cavity optomechanics provide a new platform to uncover quintessential architectures of chaos generation and the underlying physics. Here we report the generation of dynamical chaos in silicon-based monolithic optomechanical oscillators, enabled by the strong and coupled nonlinearities of two-photon-absorption induced Drude electron-hole plasma. Deterministic chaotic oscillation is achieved, and statistical and entropic characterization quantifies the chaos complexity at 60 fJ intracavity energies. The correlation dimension D2 is determined at 1.67 for the chaotic attractor, along with maximal Lyapunov exponent rate about 2.94 the fundamental optomechanical oscillation for fast adjacent trajectory divergence. Nonlinear dynamical maps demonstrate the subharmonics, bifurcations, and stable regimes, along with distinct transitional routes into chaos. This provides a CMOS-compatible and scalable architecture for understanding complex dynamics on the mesoscopic scale.