Flexible control of an ultrastable levitated orbital micro-gyroscope through orbital-translational coupling.

Introducing rotational degree of control into conventional optical tweezers promises unprecedented possibilities in physics, optical manipulation, and life science. However, previous rotational schemes have largely relied upon the intrinsic properties of microsphere anisotropy-such as birefringence or amorphous shape-which involves sophisticated fabrication processes and is limited in their application range. In this study, we demonstrated the first experimental realization of orbiting a homogeneous microsphere by exploiting angular momentum in a transversely rotating optical trap. The high level of rotational control allows us to explore orbital-translational coupling and realize an ultra-stable micro-gyroscope of considerable value. The dynamics of orbital levitated particle was theoretically characterized using a simple model. Our proposed method provided a novel way to qualitatively characterize optical trap features. In the future, the approach could pave the way for investigating rotational opto-mechanics, rotational ground state cooling, and the study of ultra-sensitive angular measurement.