Dynamics analysis of ellipsoid in a dual-beam fiber-optic trap with transverse offset

For an ellipsoid suspended in a dual-fiber optic trap with transverse offset, the optical force, torque and posture are theoretically analyzed. When importing a transverse offset between two fibers, in the water environment, the azimuthal angle between the long axis and the optical axis increases with the offset distance. In the vacuum environment, the ellipsoid will spin in the trap center. When the offset is great than the threshold, the ellipsoid will move around the trap center along an elliptic trajectory, accompanied with the spin motion. The results will contribute to better understanding of the spin motion in the transversely misaligned dual-beam fiber-optic trap.