Optics of metal nanoparticle aggregates with light induced motion

Sergey V. Perminov, A.V. Rzhanov Institute of Semiconductor Physics
V. P. Drachev, Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University
Sergey Rautian, P.N. Labedev Physical Institute

Abstract

Light-induced forces between metal nanoparticles change the geometry of the aggregates and affect their optical properties. Light absorption, scattering and scattering of a probe beam are numerically studied with Newton's equations and the coupled dipole equations for penta-particle aggregates. The relative changes in optical responses are large compared with the linear, low-intensity limit and relatively fast with nanosecond characteristic times. Time and intensity dependencies are shown to be sensitive to the initial potential of the aggregation forces.