Nonlinear cavity quantum optomechanics in the unresolved-sideband regime

A growing number of unresolved-sideband optomechanics experiments are now observing nonlinearities, which cannot be described within the linearized approximation. However, a suitable theoretical framework for describing these nonlinearities is needed for optomechanics to advance beyond the current state-of-the-art. In this talk, I will introduce our framework of cavity quantum optomechanics, which captures the nonlinearities of both the radiation-pressure interaction and the cavity response. I will then describe how this framework can be used to perform position measurement well beyond the breakdown of the linearized approximation.