Donor and acceptor modes in photonic band structure

An off-normal fibre-like texture in thin films on single-crystal substrates

“…As there are no known late Tertiary faults or extensional structures in this region [15][16][17][18][19] , we assume that this exhumation is entirely erosional. We calculated erosion rates for these samples by relating each apatite He age to cooling-ratedependent closure temperature and depth through a series of equations with assumed parameters, including geothermal gradient, He diffusion properties 20 , thermal diffusivity, and depth to constant temperature 22 (see Supplementary Information). We used sample-specific geothermal gradients based on interpolation of observed gradients ranging from 20 to 40 8C km 21 (ref.…”

Spatial homogeneity of optically switched semiconductor photonic crystals and of bulk semiconductors

“…[3] In this case, a photon may be trapped at a point defect which * Electronic address: T.G.Euser@utwente.nl † URL: www.photonicbandgaps.com serves as a cavity with a high quality factor. [5] In the examples above, the photonic crystals themselves do not change in time. Switching experiments, in which the properties of photonic crystals are modified on an ultrafast timescale allow many interesting new opportunities.…”

Controlled excitation of electromagnetic band-gap line and point defect modes at microwave frequencies

“…When a point defect is introduced in the EBG lattice by local modification of the lattice parameters, localized modes with resonant frequencies inside the band gap may exist. [5][6][7][8][9] Such localized modes have a potential to be used as a high Q resonator [10][11][12][13][14][15] for various frequency ranges from the microwave range up to optical frequencies. A linearly extended defect can guide waves with high efficiency, thus allowing for the construction of beam splitters, 16,17 sharp bend waveguides, 18 -22 and coupling structures.…”