Theoretical and Experimental Study of Surface Plasmon Radiation Force on Micrometer-Sized Spheres

We report theoretical and experimental study of surface plasmon (SP) radiation force on micrometer-sized polystyrene latex spheres with different radii. Two theoretical methods are introduced to numerically investigate the SP sphere system: the arbitrary beam theory for electromagnetic field distribution and the generalized Lorenz–Mie scattering theory for radiation force calculation. Transport velocity of the spheres in water is tested experimentally and compared with numerical results. Our work also shows effective coupling from SP field to micrometer-sized spheres, with high consistency between experiment and calculation, which has significant potential in future applications.