Speaker
Description
Two-dimensional nanomechanical resonators have been studied mainly in crystalline materials, leaving the atomically thin amorphous limit largely unexplored. Here we study this regime in suspended nanodrum resonators made from monolayer amorphous carbon (MAC), an intrinsically disordered two-dimensional membrane. Using optothermal actuation and interferometric readout, we resolve thermomechanical motion, driven resonances, and multimode spectra in vacuum. The measured devices show broad distributions in resonance frequency and quality factor, consistent with heterogeneous stress and disorder in the amorphous membrane. Under stronger drive, the resonators display rich nonlinear behavior, including hardening, softening, and mixed Duffing response, as well as nonlinear damping and parametric spectral features. In some drums, the observed responses and mode structure are further consistent with intermodal coupling and possible internal resonance. Our results establish MAC as a promising model system for probing disorder-sensitive nonlinear nanomechanics in the two-dimensional amorphous limit.