Optical forces on a spheroidal microparticle using a classical optics approximation

In this study we report a detailed description of the trapping forces exerted on an arbitrary oriented micron-sized dielectric spheroid by means of a counterpropagating dual-beam optical trap with a Gaussian transverse field pattern, using a classical optics approximation. Our analysis includes the calculation of the transverse and axial trapping efficiencies as function of the normalized beam waist separation distance, normalized spheroid size, effective index of refraction of the microparticle and ellipticity of the spheroid. The trapping forces produced are compared with those obtained for spheres.

[1]  Simon Hanna,et al.  Optical trapping of spheroidal particles in Gaussian beams. , 2007, Journal of the Optical Society of America. A, Optics, image science, and vision.

[2]  S. Chu,et al.  Observation of a single-beam gradient force optical trap for dielectric particles. , 1986, Optics letters.

[3]  Feng Xu,et al.  Theoretical prediction of radiation pressure force exerted on a spheroid by an arbitrarily shaped beam. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[4]  Julio C Gutiérrez-Vega,et al.  Helmholtz-Gauss waves. , 2005, Journal of the Optical Society of America. A, Optics, image science, and vision.

[5]  G. Arfken.  Mathematical Methods for Physicists , 1967 .

[6]  A. Ashkin,et al.  Optical trapping and manipulation of viruses and bacteria. , 1987, Science.

[7]  A. Knoesen,et al.  Trapping forces in a multiple-beam fiber-optic trap. , 1997, Applied optics.

[8]  G. Gouesbet,et al.  Generalized Lorenz-Mie theory for a spheroidal particle with off-axis Gaussian-beam illumination. , 2003, Applied optics.

[9]  Cameron Tropea,et al.  Radiation Torque Exerted on a Spheroid: Analytical Solution , 2008 .

[10]  Feng Xu,et al.  Generalized Lorenz-Mie theory for an arbitrarily oriented, located, and shaped beam scattered by a homogeneous spheroid. , 2007, Journal of the Optical Society of America. A, Optics, image science, and vision.

[11]  Pavel Zemánek,et al.  Transverse particle dynamics in a Bessel beam. , 2007, Optics express.

[12]  G. Roosen,et al.  Optical levitation by means of two horizontal laser beams: A theoretical and experimental study , 1976 .

[13]  H. Rubinsztein-Dunlop,et al.  Numerical modelling of optical trapping , 2001 .