Defect control in colloidal crystals is essential for these nanostructures to be effective as photonic bandgap (PBG) materials. We have used in-situ monitoring of the PBG of a colloidal crystal to study the structural changes during colloidal self assembly, with a focus on the formation of macroscopic defects such as cracks. These findings allow us to model the final stages of colloidal self as...

In this paper, we present the simulation results on the absorption modification in photonic crystal (PC) structures. For one-dimensional (1D) PC, using transfer matrix method (TMM), we obtained enhanced absorption in both defectfree and defect based PC structures. High absorption (>60%) and small bandwidth (< 0.1 λ0) at defect level were observed with optimal absorption layers of 10-15 for stru...

By adding a point defect to a photonic crystal structure, a microcavity can be made to trap electromagnetic energy with wavelength inside the photonic bandgap (PBG). This property together with other unique properties of photonic crystals enables us to control the propagation and spectrum of transmitted wave inside the photonic crystal waveguiding structures and to design and implement microsca...

We demonstrate a spectrally discrete white-light laser device based on a photonic bandgap hybrid, which is composed of a soft photonic crystal; i.e., a layer of dye-doped cholesteric liquid crystal (CLC), sandwiched between two imperfect but identical, inorganic multilayer photonic crystals. With a sole optical pump, a mono-, bi-, or tri-chromatic laser can be obtained and, through the soft pho...

In this paper, we have systematically studied the holographic fabrication of three-dimensional (3D) structures using a single 3D printed reflective optical element (ROE), taking advantage of the ease of design and 3D printing of the ROE. The reflective surface was setup at non-Brewster angles to reflect both sand p-polarized beams for the interference. The wide selection of reflective surface m...

Efficient silicon-based light sources are expected to be key devices for applications such as optical interconnection. Huge number of researches has been conducted for realizing silicon-based light sources. Most of them utilized silicon-related materials such as silicon nanostructures or germanium, not crystalline silicon, which has been considered as a poor light emitter because of its indirec...

A fully planar two-dimensional optomechanical crystal formed in a silicon microchip is used to create a structure devoid of phonons in the GHz frequency range. A nanoscale photonic crystal cavity is placed inside the phononic bandgap crystal in order to probe the properties of the localized acoustic modes. By studying the trends in mechanical damping, mode density, and optomechanical coupling s...

We report the use of an optical interference holographic setup with a five-beam configuration, consisting of four side beams and one central beam from the same half space, to fabricate woodpile and diamond structures for the use as photonic bandgap materials in which electromagnetic waves are forbidden in the bandgap. By exploiting the advantage of the binarization of the interference pattern, ...