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We will give an overview of recently observed analogies between the transport of electrons and light waves and show how complex photonic materials, ranging from periodic to disordered structures can be applied as photonic devices.
Light propagation in slab photonic crystals can have a negative phase velocity and accumulate a negative optical path length. We present experimental results on guiding and dispersion properties when the phase index is approximately -1.
We have experimentally obtained the reflection transfer function of a phononic bandgap nano-crystal including phase information by using a single-quantum-well in a phonon cavity. Our time-domain investigations help to resolve the apparent ldquosuperluminalrdquo paradox.
A one-dimensional photonic bandgap lattice consisting of 72 periodically-cascaded microrings was fabricated in benzocyclobutene. A wide bandgap of 1.6 nm and extinction > 20dB were achieved. The device exhibited low transmission loss even after 72 microrings.
Using an anisotropic plane-wave expansion method first worldwide theoretical evidence of spectral band structure asymmetry (omega(k)neomega(-k)) and band gap tunability (as a function of magnetization direction) is obtained for 2-dimensional magneto-photonic crystals.
Enhancement and suppression of spontaneous emission in certain directions near the bandgap is observed for dye molecules in the centre of tapered photonic crystal fibres, as predicted by LDOS calculations, but not by the bandstructure.
We combine chemically-synthesized single nanowire emitters with lithographically-defined photonic crystal structures. Localized emission from engineered defects and light suppression in regions of the photonic crystal are demonstrated by photoluminescence imaging and spectroscopy measurements.
We demonstrate a ring-shaped Bessel-like photonic lattice akin to a photonic bandgap fiber with a low-index core. While the lattice is optically induced with self-defocusing nonlinearity, bandgap guidance of a probe beam is clearly observed.
We report on the propagation of high peak power higher-order solitons and their break up due to Raman scattering and third order dispersion over 30 m in hollow core photonic bandgap fibers.
We demonstrate the formation of long period gratings in fluid-filled photonic bandgap fiber (PBGF). The unique modal properties of PBGFs allow for coupling to LP11-like modes at multiple wavelengths. We obtain good agreement with simulations.
We use light-induced atomic desorption to produce an appreciable density of Rubidium atoms in a hollow-core photonic bandgap fiber and demonstrate electromagnetically induced transparency at very low light levels.
We have developed a vectorial quantum model of spontaneous parametric down-conversion in one-dimensional nonlinear photonic-band-gap structures that shows that these structures represent a promising perspective source of entangled two-photon states.
The second- and third-harmonics enhancement in birefringent silicon-based photonic crystals and microcavities at the photonic band gap edge due to fulfilment of phase matching condition is controlled due to anisotropy of porous silicon dielectric function.
We investigated the magnetic resonance of split-ring resonators (SRR) experimentally. The dependence of the geometrical parameters on the resonance frequency of SRR is studied. We further investigated the effect of disorder on performance of SRRs.
A novel heterojunction thermophotovoltaic device, converting infrared radiation to electricity, has been demonstrated with a room-temperature open-circuit voltage of 360 mV, the highest demonstrated for a 0.54-eV-bandgap device.
3D and 1D magnetophotonic crystals based on opals impregnated by Bi-substituted iron-yttrium garnet (Bi:YIG) and Bi:YIG-SiO2 paired multilayer structures are fabricated. Magnetization-induced effect (nonlinear magneto-optical Kerr effect) in secondand third-harmonic generation is observed.
A UV ZnO light-emitting diode was realized by using a ZnO p-n homojunction. The ZnO LED showed clear rectification with a threshold voltage of 3.2 V and a UV light emission at 380 nm.
We found that in low loss SOI sub-micron photonic wire racetrack resonators, when the air gap between the resonator and access waveguide is < 120 nm, the mode conversion losses in the coupling region dominate bending and propagation losses.
The 2D THz photonic bandgap structures are fabricated of cured SU-8, and installed in single mode metal parallel plate waveguides. The structures are characterized by THz time-domain spectroscopy. The experimental measurements agree with theoretical predictions.
Modified designs for hollow-core bandgap fibers with suppressed higher-order modes are proposed. Numerical simulations demonstrate that index-matched cladding defects can dramatically increase losses of undesirable modes and leave the fundamental well confined.
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