Date of Degree
The subject of this thesis is the opto-mechanical interaction of a spherical high-Q microresonator and a subwavelength particle, which, at optical wavelengths, corresponds to a size on the order of nanometers. After a review of the basic theory of spherical resonators and multi-sphere scattering, the full self-consistent electromagnetic field of the coupled resonator-particle system is derived. The particle-induced frequency shift and broadening is calculated by examining the poles of the scattering coefficients of the resonator. The force exerted on the particle by the field is determined via the Maxwell stress tensor, and is found to be in general non-conservative. From the force, the trajectories of the particle positioned outside the resonator are investigated. The relationship between frequency shift and the conservative and non-conservative components of the force is found to differ from the well-known formulas for the "gradient" and "scattering" force, which are commonly derived by neglecting the modification of the resonator field by the particle. The key aspects of this difference are investigated by re-deriving the results of the exact field calculations from a modified gradient/scattering framework, which explicitly takes into account the modification of the resonator field due to the particle.
Rubin, Joel T., "Optomechanics of Cavity Driven Nanoparticles" (2012). CUNY Academic Works.