Photonic crystals are periodic dielectric structures where the period is of the same order of magnitude than the wavelength of light. As a result of interference, there exist band gaps for light, i.e., light of certain range of frequencies is not allowed to exist inside the photonic crystal, which can be used to control and confine light. In this thesis, photonic crystals were studied with comp...

Under rapid urbanization, many cities in China suffer from serious fine particulate matter (PM2.5) pollution. As the emission sources or adsorption sinks, land use and the corresponding landscape pattern unavoidably affect the concentration. However, the correlation varies with different regions and scales, leaving a significant gap for urban planning. This study clarifies the correlation with ...

Volume 3, Issue 4, April 2014 Page 346 Abstract Dense Wavelength Division Multiplexing (DWDM) is a promising technique which can meet the increasing demand for communication bandwidth. It multiplexed all the channel signals onto single fiber thus increases the capacity of existing fiber. It is a perfect substitute for long haul networks. The major problem that DWDM technique suffered is dispers...

A 90-nm wideband (1500-1590nm) optical amplifier consisting of a dispersion-compensated-fiber-based Raman fiber amplifier and a semiconductor optical amplifier with gain clamping and dispersion compensation is demonstrated for wide bandwidth amplification with gain flatness as well as dispersion compensation. 10Gb/s DWDM transmission over 100km conventional single-mode fiber link with low biter...

We study dispersion properties of photonic crystal fibers for their use in coherent light generation in visible wavelengths through optical parametric amplification. We use a simple 2D cross-sectional model of the holey fiber and solve for the guided modes. The models developed in this study of PCFs allow us to tailor the dispersion profile of PCFs using the geometric parameters of the fiber. W...

We reveal experimentally waveguiding characteristics and group-velocity dispersion of line defects in photonic crystal slabs as a function of defect widths. The defects have waveguiding modes with two types of cutoff within the photonic band gap. Interference measurements show that they exhibit extraordinarily large group dispersion, and we found waveguiding modes whose traveling speed is 2 ord...

Color dispersion, i.e., the dependency of refractive index of any transparent material on the wavelength of light, has important consequences for the function of optical instruments and animal eyes. Using a multi-objective goal attainment optimization algorithm, a dispersion model was successfully fitted to measured refractive indices of various ocular media and the longitudinal chromatic aberr...

Adaptive optics is used to compensate for modal dispersion in digital transmission through multimode fiber (MMF). At the transmitter, a spatial light modulator (SLM) controls the launched field pattern. An estimate of intersymbol interference (ISI) caused by modal dispersion is formed at the receiver and fed back to the transmitter, where the SLM is adjusted to minimize ISI. Error-free transmis...

We measure group delay and group velocity dispersion of silica colloidal photonic crystals in the near-infrared with white light interferometry. While group delay and group velocity dispersion increase with sample thickness, scattering on sample imperfections is found to counteract this development, resulting in group delays lower than theoretically expected. For thin photonic crystals, group v...