Optical properties of nanostructures: From random to periodic.

摘要

Nanostructures can change optical properties of materials such as optical dispersion and transmission and reflection via scattering and interference. By engineering the degree of order in various dielectric and metallic nanostructures, I demonstrate that light propagation, spontaneous emission, localization and lasing can be controlled.;In the first part of this thesis (chapter 1), the basic concepts of optical scattering and emission in nanostructures are introduced. Fundamental properties of photonic crystals are presented including photonic bandgaps and dispersion of light. Physical properties of surface plasmons are also briefly described.;In the second part of the thesis (from chapter 2 to chapter 5), I describe experimental investigations and theoretically analyze optical properties of photonic crystals, quasi-ordered dielectric structures in avian feathers and random metal structures. We demonstrate, (1) room temperature lasing in the near-ultraviolet (UV) frequency in ZnO inverse opal photonic crystals (2) spontaneous emission enhancement caused by the frozen mode at a stationary inflection point of a dispersion curve in ZnO inverse opal photonic crystals (3) structure color creation by single and double scattering from the quasi-ordered structures of avian feathers (4)propagation and localization of surface plasmons in semi continuous metal films;The last part of the thesis (chapter 6), is the conclusion.