Nonlinear mechanics with photonic crystal nanomembranes

TL;DR

This paper demonstrates nonlinear effects in photonic crystal nanomembranes, highlighting their potential for advanced optomechanical applications and exploring their nonlinear dynamics and nonlocal behaviors.

Contribution

The study introduces the fabrication and characterization of photonic crystal nanomembranes exhibiting nonlinear mechanical effects, advancing understanding of their nonlinear dynamics and nonlocal responses.

Findings

Observation of nonlinear behavior in a single mechanical mode

Detection of nonlocal frequency shifts between modes

Characterization of phase-space trajectories during ring-down

Abstract

Optomechanical systems close to their quantum ground state and nonlinear nanoelectromechanical systems are two hot topics of current physics research. As high-reflectivity and low mass are crucial features to improve optomechanical coupling towards the ground state, we have designed, fabricated and characterized photonic crystal nanomembranes, at the crossroad of both topics. Here we demonstrate a number of nonlinear effects with these membranes. We first characterize the nonlinear behavior of a single mechanical mode and we demonstrate its nonlocal character by monitoring the subsequent actuation-related frequency shift of a different mode. We then proceed to study the underlying nonlinear dynamics, both by monitoring the phase-space trajectory of the free resonator and by characterizing the mechanical response in presence of a strong pump excitation. We observe in particular the frequency evolution during a ring-down oscillation decay, and the emergence of a phase conjugate mechanical response to a weaker probe actuation. Our results are crucial to understand the full nonlinear features of the PhC membranes, and possibly to look for nonlinear signatures of the quantum dynamics.