Radiation pressure induced by an evanescent field was experimentally analyzed for a single submicrometer-sized gold particle. The force measurement was based on a thermodynamic analysis of Brownian motion by use of a three-dimensional position-sensing technique. The lateral radiation pressure could be ascribed to a scattering force, which was oriented in the same direction as the propagation vector of the incident laser beam. The potential profile in the longitudinal direction indicated that the gold particle was attracted to the high-intensity region of the evanescent field by a gradient force.
© 2000 Optical Society of America
(120.3930) Instrumentation, measurement, and metrology : Metrological instrumentation
(140.7010) Lasers and laser optics : Laser trapping
(260.3910) Physical optics : Metal optics
(290.5850) Scattering : Scattering, particles
Keiji Sasaki, Jun-ichi Hotta, Ken-ichiro Wada, and Hiroshi Masuhara, "Analysis of radiation pressure exerted on a metallic particle within an evanescent field," Opt. Lett. 25, 1385-1387 (2000)