Sökning: "photonic crystal"
Visar resultat 1 - 5 av 40 avhandlingar innehållade orden photonic crystal.
1. InP-based photonic crystals : Processing, Material properties and Dispersion effects
Sammanfattning : Photonic crystals (PhCs) are periodic dielectric structures that exhibit a photonic bandgap, i.e., a range of wavelength for which light propagation is forbidden. The special band structure related dispersion properties offer a realm of novel functionalities and interesting physical phenomena. LÄS MER
2. Photonic crystals and photocatalysis : Study of titania inverse opals
Sammanfattning : Due to an increase of human activity, an increase health risk has emerged from the presence of pollutants in the environment. In the transition to renewable and sustainable life style, treatment of pollutants could support the shifting societies. LÄS MER
3. Computational methods for the analysis and design of photonic bandgap structures
Sammanfattning : In the present thesis, computational methods for theanalysis and design of photonic bandgap structure areconsidered. Many numerical methods have been used to study suchstructures. Among them, the plane wave expansion method is veryoften used. LÄS MER
4. 3D Magnetic Photonic Crystals : Synthesis and Characterization
Sammanfattning : This thesis presents the synthesis methods and the characterizations of magnetic Fe3O4 nanoparticles, silica spheres with Fe3O4 nanoparticles embedded, and three dimensional magnetic photonic crystals (MPCs) prepared from the spheres. The structure, material composition, magnetic and optical properties, photonic band gaps (PBGs), as well as how these properties depend on the concentration of the magnetic nanoparticles, are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), superconducting quantum interference device (SQUID), Faraday rotation (FR) and optical spectrophotometers. LÄS MER
5. Carbon-nanofibre-based tunable photonic crystals
Sammanfattning : Photonic crystals are materials with periodically varying refractive indices. In conventional photonic crystal design it is hard to achieve tunable structures in the visible range. That is, structures with changeable optical properties. LÄS MER