Abstract

In cavity optomechanical systems, the motion of a mechanical element is sensed by its influence on the field within an electromagnetic resonator. While their experimental realizations are quite diverse, with mechanical elements ranging from picogram-scale nanofabricated filaments to the kilogram-scale mirrors of the LIGO detector and optical systems ranging from stripline resonators to kilometers-long optical cavities, such systems are converging on the common goal of quantum limited operation. I will discuss the use of ensembles of ultracold trapped atoms as mechanical elements within a high-finesse optical cavity. With this system, we have observed distinctly quantum mechanical properties of both the “opto” and “mechanical” parts of our quantum cavity optomechanical system. Connections to the dynamics of spin ensembles within optical resonators will also be discussed.