Dynamic Analysis and Simulation of an Optically Levitated Rotating Ellipsoid Rotor in Liquid Medium

Abstract

Optical trap, a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness. Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-freedom. In this work, we analyzed the feasibility of applying optically levitated rotor in the system. We presented the dynamic analysis and simulation of an ellipsoid micron particle. The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed. We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided. Furthermore, the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated. We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor. These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers, especially to the future research of the gyroscope effect.

Fabrication and Manipulation of Non-Spherical Particles in Microfluidic Channels: A Review

“…Utilizing the laser tweezers as a tool to tear the adherent RBC off from the endothelial cell, Kapkov et al [ 55 ] carried out the measurements of the interaction forces between the individual RBC and the endothelial cell. Another interesting application of optical tweezers is to trap an ellipsoid micron particle as an optically levitated rotor which can be analog to a liquid floated gyroscope [ 56 ]. Researchers using optical tweezers on non-spherical particles mainly focus on particle rotation and cell–cell interaction.…”