ABSTRACT
We demonstrate the existence of strong Anderson localization in certain disordered phononic systems. As a result, the transmission coefficient of elastic waves through a slab of the material practically vanishes, whatever the angle of incidence, over a region of frequency much wider than the absolute frequency gap of the corresponding ordered system. The phenomenon can be of use in the design of phononic systems with very wide absolute transmission gaps.
ABSTRACT
Stacking faults appear to be the most common type of defect in inverted opals which are good candidates for photonic crystals with absolute gaps in the visible range of light. In this Letter we present for the first time a systematic study of the effect of stacking faults on the optical properties of self-assembled photonic crystals, by means of large-scale transmittance calculations for macroscopic slabs of inverted opals with randomly distributed stacking faults. We show that frequency gaps, as seen in optical transmission experiments, will in general appear wider in the presence of stacking faults. We attribute the above to Anderson localization of light due to disorder.
ABSTRACT
A brief introduction of the layer-Korringa-Kohn-Rostoker method for calculations of the frequency band structure of photonic crystals and of the transmission and reflection coefficients of light incident on slabs of such crystals is followed by two applications of the method. The first relates to the frequency band structure of metallodielectric composites and demonstrates the essential difference between cermet and network topology of such composites at low frequencies. The second application is an analysis of recent measurements of the reflection of light from a slab of a colloidal system consisting of latex spheres in air.
