Nonlinear dynamic control of GaAs nanomechanical resonators using lasers.

The ability to control, manipulate, and read out nanomechanical resonators is of great significance for many applications. In this work, we start by constructing a nonlinear dynamic model that is deduced from the fundamental beam-photon-electron interaction and energy band theories, with the aim of describing a complicated cavity-free optomechanical coupling process. Based on the model established, we first reveal the manipulation of a resonator's response, including softening and hardening effects due to laser injection. By driving the laser parametrically, we comprehensively investigate the control of the resonator's dynamics, in particular, in the nonlinear regime. It is found that both the laser power and frequency can be used to directly manipulate the NEMS resonator's dynamics, e.g., by amplitude amplification, periodicity changes, and periodic-chaotic state conversion. We then provide bifurcation diagrams, which evidence a deterministic evolution of dynamics. Finally, we perform a special study of the control of chaotic states of the nanomechanical resonator using laser parametric driving. The maximal Lyapunov exponents together with time series calculation show that the chaotic states can be controlled at a few specific frequency points of the injecting laser. This work not only provides guidance for using lasers to control nanoscale resonators, but also sheds light on the exploration of novel applications based on nonlinear NEMS resonators.