Rotation dynamics of a uniaxial birefringent cylinder in an optical tweezer with a rotating polarization ellipse

Huachao Yu and Weilong She

We make a theoretical investigation on the rotation dynamics of a uniaxial birefringent cylinder in an optical tweezer with a rotating polarization ellipse. Analytical results have been obtained for the cylinder suspended in fluid with a low Reynolds number. They show that there are two distinct rotational states of the cylinder. In one state, the optical axis of the cylinder rotates synchronously with the rotating polarization ellipse. In another state, the optical axis rotates at a time-periodic angular velocity. We find that such a rotation feature is rooted in the angular dependence of the radiation torque exerted on the cylinder. We also notice that the transmitted light through the cylinder carries the information of rotation angle of the cylinder, which enables one to measure quantities such as the cylinder’s angular velocity and its period by detecting the power of the transmitted light.

DOI