We demonstrate that multiple topological transitions that occur, with high-sensitivity, by continuous change in geometry of a simple 2D dielectric-frame photonic crystal consisting of circular air-holes. These transitions are characterized by the switch between the frequencies of the pand d-orbital Bloch modes encompassing the photonic band gap (PBG). By tuning the radii of the holes and/or the...

here, we propose an add-drop and a channel drop filter based on two-dimensional photonic crystal all circular ring resonators. these structures are made of a square lattice of silicon rods with the refractive index n1=3.464 surrounded by air (with refractive index n2=1). the broadest photonic band gap occurs at the filling ratio of r/a = 0.17. two linear defect w1 waveguides couple to the ring....

We study theoretically the band-gap structures of several types of three-dimensional photonic crystals with the fcc lattice symmetry: synthetic opals, inverted yablonovite and woodpile. The samples of inverted yablonovite, inverted yablonovite with a glassy superstructure and woodpile are fabricated by two-photon polymerization through a direct laser writing technique, which allows the creation...

We show that Dirac points can emerge in photonic crystals possessing mirror symmetry when band gap closes. The mechanism of generating Dirac points is discussed in a two-dimensional photonic square lattice, in which four Dirac points split out naturally after the touching of two bands with different parity. The emergence of such nodal points, characterized by vortex structure in momentum space,...

We investigate the photonic properties of one dimensional photonic crystals realized on Silicon On Insulator channel slot-waveguide to engineer slow light effects. Various geometries of the photonic pattern have been characterized and their photonic band-gap structure analyzed. The optimal geometry has been further used to realize a coupled resonator optical waveguide (CROW). A first optimizati...

The fundamental and higher frequency global photonic band gaps are obtained for transverse electric (TE) and transverse magnetic (TM) modes in photonic band gap (PBG) structures consisting of two-dimensional (2D) square and triangular lattices of perfectly conducting cylinders. The global photonic band gaps in metallic lattice, which are found to differ qualitatively as well as quantitatively f...

We describe a new photonic-crystal structure with a complete three-dimensional photonic band gap (PBG) and its potential application to integrated optics. The structure not only has a large band gap and is amenable to layer-by-layer litho-fabrication, but also introduces the feature of high-symmetry planar layers resembling two-dimensional photonic crystals. This feature enables integrated opti...

This paper is a survey of our recently published and new results on nonlinear-optical studies of photonic band-gap (PBG) structures formed from mesoporous silicon. The studies are performed on photonic crystals, high-quality-factor microcavities (MC) with a half-wavelength-thick microcavity spacer, and on series of coupled microcavities with two identical microcavity spacers and controllable co...

We describe the role of first non-Markovian corrections to resonance fluorescence in photonic crystals, using a perturbative expansion of the Heisenberg equations of motion in powers of the atom-field reservoir coupling strength. Non-Markovian effects arise from the rapid variation of the photonic density of states with frequency. Our method recaptures the physics of the photon-atom bound state...

A facile method to realize photo-responsive inverse opal photonic crystal polymer (IOPP) films with an adjustable broad-wavelength-range photonic band gap (PBG) was demonstrated in this communication. When immersing the IOPP film in malachite green carbinol base (MGCB) solution, under light irradiation, the MGCB released hydroxide ions. In this way, optical signals were converted to chemical si...