waveguides with low confinement loss, low chromatic dispersion, and low nonlinear effects are used in optical communication systems. optical fibers can also be employed in such systems. besides optical fibers, photonic crystal fibers are also highly suitable transmission media for optical communication systems. in this paper, we introduce two new designs of index-guiding photonic crystal fiber ...

We reported an ultrahigh birefringence PCF with a germanium-doped elliptical core, which is fabricated in our lab using the stack-and-draw method, and an ultrahigh birefringence of 1.1×10 is obtained experimentally via FBG and Sagnac loop. OCIS codes: (060.2280) Fiber design and fabrication; (060.5295) Photonic crystal fibers; (060.3735) Fiber Bragg gratings

Optical fibers in which gain-guiding effects are significant or even dominant compared with conventional index guiding may become of practical interest for future high-power single-mode fiber lasers. I derive the propagation characteristics of symmetrical slab waveguides and cylindrical optical fibers having arbitrary amounts of mixed gain and index guiding, assuming a single uniform transverse...

Extant studies have presented various indexes for evaluating urban carrying capacity (UCC), but there is no consistent perspective on UCC. This paper presents a guiding index framework from holistic as reference guidance (UCC). The developed based upon the theory of sustainable development by addressing fundamental question what capacities are needed to enable development. composed three-layer ...

1. The photonic-crystal fibres In conventional optical fibres, electromagnetic modes are guided by a phenomenon of total internal reflection on a core-cladding border. The core refractive index is higher than the refractive index of a cladding which is achieved by adequate doping of a central part of the based material [1]. After over 20 years of intense researches on optical fibres, including ...

We experimentally demonstrate a novel silicon waveguide structure for guiding and confining light in nanometer-wide low-refractive-index material. The optical field in the low-index material is enhanced because of the discontinuity of the electric field at high-index-contrast interfaces. We measure a 30% reduction of the effective index of light propagating in the novel structure due to the pre...

We consider an air-silica honeycomb lattice and demonstrate a new approach to the formation of a core defect. Typically, a high or low-index core is formed by adding a high-index region or an additional air-hole (or other low-index material) to the lattice, but here we discuss how a core defect can be formed by manipulating the cladding region ratherthan the core region itself. Germanium-doping...