INDUCED MULTIPOLE RESONANCES BY INTERACTING NANO-SCATTERERS

• Main Author: Perdana, Nanda
• Format: Theses
• Language: Indonesia
• Subjects: Fisika
• Online Access: https://digilib.itb.ac.id/gdl/view/46195
• Institution: Institut Teknologi Bandung

In this thesis, electromagnetic wave scattering response by two cubes dielectric scatterers is studied. Many optical phenomena and applications use complex shaped scatterers. Theoretically, wave scattering phenomena by a sphere scatterer, can be explained by Mie scattering theory. However, there is no comprehensive theory that explains for the scatterers that have nonspherical shapes. Therefore, in this thesis, electromagnetic wave scattering by a single nano-scatterer with shape variations is done. Numerically, the scattered electric and magnetic field expression can be generated by an electromagnetic computation method, such as the surface integral equation method. This method has lower computation requirement, without decreasing the calculation accuracy and can be used for nano-scatterers which have high permittivity. Scattered electromagnetic wave is then analyzed by multipole expansion theory, in which the scattered wave is stated as the expansion of orthogonal basis functions and its scattering coefficients. The derivation of analytical multipolar expression is compared with the result of a cube scatterer. Further, the induced multipolar contribution due to interaction of two cube scatterers system is studied. Lorentz oscillator model fitting procedure is applied to study this phenomenon further. Fitting results show damped harmonic oscillation pattern of the resonances caused by the scattered field interference.