Analytical model for transmission dips in self-assembled two-dimensional colloidal crystals.

Self-assembled two-dimensional (2D) colloidal crystals (CCs) are utilized in various optical devices, lasers, biosensors, and light harvesting applications. Optical design tuning capabilities, in terms of sphere refractive index and diameter size, can influence the optical characteristics for the close-packed single-layer or multilayer structures. Often transmission dips in 2D CCs are observed, which cannot be explained by Bragg diffraction as it does for 3D photonic crystals.

Modeling disorder in two-dimensional colloidal crystals based on electron microscope measurements.

Self-assembled two-dimensional colloidal crystals (CCs) are critical components in many optical and optoelectronic devices. Such structures usually exhibit various types of disorder, which sometimes can be beneficial for the desired applications. However, disorder poses challenges to the modeling of two-dimensional structures.

On Chip Optical Modulator using Epsilon-Near-Zero Hybrid Plasmonic Platform.

In this work, we propose a micro-scale modulator architecture with compact size, low insertion loss, high extinction ratio, and low energy/bit while being compatible with the silicon-on-insulator (SOI) platform. This is achieved through the utilization of epsilon-near-zero (ENZ) effect of indium-tin-oxide (ITO) to maximize the attainable change in the effective index of the optical mode. It also exploits the ITO layer in a hybrid plasmonic ring resonator which further intensifies the effect of the changes in both the real and imaginary parts of the effective index.

In-plane coupled Fabry-Perot micro-cavities based on Si-air Bragg mirrors: a theoretical and practical study.

In-plane Fabry-Perot cavities based on deeply etched Bragg mirrors are used in many microphotonic applications including sensing, telecom, and swept laser devices. A main limitation to their performance is the small free spectral range (FSR) and low finesse. The FSR limits the dynamic range or the wavelength tuning range, while the linewidth limits the resolution.

Enhancing the absorption capabilities of thin-film solar cells using sandwiched light trapping structures.

A novel structure for thin-film solar cells is simulated with the purpose of maximizing the absorption of light in the active layer and of reducing the parasitic absorption in other layers. In the proposed structure, the active layer is formed from an amorphous silicon thin film sandwiched between silicon nanowires from above and photonic crystal structures from below. The upper electrical contact consists of an indium tin oxide layer, which serves also as an antireflection coating.