The generation of large-amplitude coherent states of a massive mechanical resonator, and their quantum-limited detection represent useful tools for quantum sensing and for testing fundamental physics theories. In fact, any weak perturbation may affect the coherent quantum evolution of the prepared state, providing a sensitive probe for such a perturbation. Here we consider a cavity optomechanical setup and the case of the detection of a weak mechanical nonlinearity. We consider different strategies, first focusing on the stationary dynamics in the presence of multiple tones driving the system, and then focusing on non-equilibrium dynamical strategies. These methods can be successfully applied for measuring Duffing-like material nonlinearities, or effective nonlinear corrections associated with quantum gravity theories.
@article{arxiv.2504.07486,
title = {Large amplitude mechanical coherent states and detection of weak nonlinearities in cavity optomechanics},
author = {Wenlin Li and Paolo Piergentili and Francesco Marzioni and Michele Bonaldi and Antonio Borrielli and Enrico Serra and Francesco Marin and Francesco Marino and Nicola Malossi and Riccardo Natali and Giovanni Di Giuseppe and David Vitali},
journal= {arXiv preprint arXiv:2504.07486},
year = {2025}
}