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Recent results of a theoretical treatment of disorder-induced losses in photonic crystal (PhC) slabs are presented. The formalism is based on a guided-mode expansion method with a perturbative treatment of coupling to leaky PhC modes. Propagation losses are calculated for line-defect waveguides in PhC slabs defined in a high-index membrane, in particular for W1 and W1.5 waveguides in the triangular...
Electromagnetic properties of artificial media formed by lattices of thin conducting straight wires (referred to as wire media, WM) are discussed. Wire media can be described in terms of effective permittivity, which is negative at low frequencies that gives background to call it as "artificial plasma". Strong spatial dispersion is inherent in WM and it determines their main properties....
In this talk two new sub-classes of photonic bandgap materials, a) curvilinear-lattice photonic crystals, whose distinctive feature is that their individual scatterers are arranged in a curvilinear lattice and b) variable size photonic bandgap structures are introduced. We show that adhering to some restrictions in the acceptable lattice transformations, one can achieve omni-directional photonic bandgaps...
An extension of the method of single expression (MSE) for analysis of materials with complex permittivity and permeability is presented. Along with the real and imaginary parts of permittivity both the real and imaginary parts of permeability are taken into account in the MSE without any approximations. Any combination of signs (positive or negative) for complex permittivity and permeability can be...
Finite difference time domain (FDTD) and finite element (FE) frequency domain methods are used to study the propagation of arbitrary chirped pulses in photonic crystal (PhC) waveguide. An arbitrary chirped pulse is derived from a separate Semiconductor optical amplifier (SOA) model and is passed through a mini-stop band (MSB) in a photonic crystal waveguide. Good agreement is shown between the FDTD...
We analyse the difference of the effective indices and radiation loss of the two modes with identical field distribution propagating in dual-core microstructure fibres as well as their polarisation behaviour in dependence on the fibre parameters (air hole diameter, hole separation, distance between guiding cores) and bend. The optimisation of the parameters of such fibres using as vector bend sensors...
We have developed an ultra-bright pair-photon source using four wave mixing in micro-structured fibres. This source can serve as a new universal source for quantum information experiments. Using photon pairs created by four-wave mixing, we demonstrate non-classical interference between two separated sources and preliminary evidence for entangled photon pair generation both with high counting rate
The effects of the coherence properties of light beams propagating through periodic structures are discussed. In particular, spatial coherence may influence the transmitted field. Some 2D structures which give transmittances strongly influenced by the coherence of the incoming field are discussed
We have developed a vectorial quantum model of spontaneous parametric down-conversion in one-dimensional nonlinear photonic-band-gap structures. According to the obtained results these structures represent a promising perspective source of entangled two-photon states. In particular, entangled two-photon states antisymmetric in frequencies can be generated. Such entangled photons behave in the way...
We investigate the quantum-optical interplay of two-dimensional (2D) planar photonic crystals with localized emitters. Due to the spatial variation of the photonic density of states in the photonic crystal unit cell the spontaneous emission properties dependent strongly on the location of the emitter. We infiltrate nanospheres doped with small dye molecules as localized probes into 2D hexagonal Nb...
We describe a practical implementation of a semi-deterministic photon gun based on the stimulated Raman adiabatic passage pumping and the nonlinear tuning of the photonic density of states in a photonic band-gap material. We show that this device allows deterministic and unidirectional production of single photons with a high repetition rate of the order of 100 kHz. We also discuss specific 3D photonic...
The paper deals with the possibility of using photonic crystals for sensing purpose. The optical properties of photonic crystals allow to realize sensing devices characterized by a high degree of compactness and a good resolution of the quantity to detect. A particular attention is devoted to force/pressure sensors and the design of a PhC microcavity pressure sensor is reported
We consider an index-guiding silica photonic crystal fiber with a triangular hole-pattern and a periodically poled quadratic nonlinearity. By tuning the pitch and the relative size of the holes, second-harmonic generation with zero group-velocity mismatch is found to be feasible for any fundamental wavelength above 780 nm. The phase-velocity mismatch has a lower limit with coherence lengths in the...
Supercontinuum generation in a capillary tube infiltrated with a nematic liquid crystal is investigated theoretically in the near infrared region. A liquid crystal with a high electronic nonlinearity is chosen, which makes it possible to generate 100 nm wide supercontinua using IO ps pulses with peak power 1.5 kW in a 10 cm long waveguide. The possibility of tuning the spectrum of the generated Supercontinuum...
We show that index guided and photonic bandgap holey fibers of specific construction can be used as a wide-band fiber-optic polarizers. Similarly to traditional polarizing fibers, the operation principle of the index guided PCF polarizers is related to the difference in cut-off wavelengths of the two orthogonally polarized fundamental modes. Several fiber structures were analyzed and optimized for...
Colloidally synthesized CdSe/ZnS core/shell semiconductor nanocrystals (NCs) show highly efficient, narrow-width and size-tunable luminescence. Moreover, they can be incorporated in polymer matrices and deposited on solid substrates by means of spin-coating techniques. When embedded between two mirrors a NCs/polymer blends microcavity is realised, thus allowing to tailor the photoluminescence spectrum...
Dielectric spheres synthesised for the fabrication of self-organized photonic crystals such as opals offer large opportunities for the design of novel nanophotonic devices. In this paper, we show a hexagonal superlattice monolayer of dielectric spheres inscribed on a 3D colloidal photonic crystal by e-beam lithography. The crystal is produced by a variation of the vertical drawing deposition method...
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