A certain class of photonic crystals with conical dispersion is known to behave as isotropic zero-refractive-index medium. However, the discrete building blocks in such photonic crystals are limited to construct multidirectional devices, even for high-symmetric photonic crystals. Here, we show multidirectional emission from low-symmetric photonic crystals with semi-Dirac dispersion at the zone ...

We report beaming and enhanced transmission of electromagnetic waves by use of surface corrugated photonic crystals. The modes of a finite-size photonic crystal composed of dielectric rods in free space have been analyzed by the plane-wave expansion method. We show the existence of surface propagating modes when the surface of the finite-size photonic crystal is corrugated. We theoretically and...

Coherent coupling of optical resonances in spherical microcavities results in the formation of so called photonic molecules. The name originates from the analogy to chemical molecules. The coupled optical modes are similar to the atomic orbitals of a chemical molecule. In this work, we studied the resonance spectrum of the symmetric photonic molecules. Furthermore, symmetric directional emissio...

In this work, we have experimentally and theoretically studied negative refraction of electromagnetic waves by a metallodielectric photonic crystal. We showed that by adding a periodic dielectric perturbation to the unit cell of a metallic photonic crystal, it is possible to increase the range of incidence angles at which the electromagnetic waves are negatively refracted. We obtained negative ...

Photo-electrochemical water splitting is a very promising and environmentally friendly route for the conversion of solar energy into hydrogen. However, the solar-to-H2 conversion efficiency is still very low due to rapid bulk recombination of charge carriers. Here, a photonic nano-architecture is developed to improve charge carrier generation and separation by manipulating and confining light a...

Invisible photonic printing, an emerging printing technique, is particularly useful for steganography and watermarking for anti-counterfeiting purposes. However, many challenges exist in order to realize this technique. Herein, we describe a novel photonic printing strategy targeting to overcome these challenges and realize fast and convenient fabrication of invisible photonic prints with good ...

This thesis concerns two classes of photonic crystal that differ from the usual solid-state dielectric photonic crystals studied in optical physics. The first class of unconventional photonic crystal consists of atoms bound in an optical lattice. This is a “resonant photonic crystal”, in which an underlying optical resonance modifies the usual band physics. I present a three-dimensional quantum...

Photonic crystals have demonstrated potential for application in many fields and devices. We demonstrate practical fabrication of three-dimensional photonic crystals using the glancing angle deposition thin film fabrication technique. Optical characterization provides strong evidence for the existence of a complete photonic band gap in three dimensions, centered at 1.6 m. We also investigate th...

It is firmly established that periodic lattice structures can support photonic bandgaps (PBG). However, complete and absolute photonic bandgaps (CAPBG) have only been achieved in high dielectric constant mediums such as GaAs (o=13.6). An artificial quasiperiodic photonic crystal based on the random square-triangle tiling system was designed and fabricated. The photonic quasicrystal possesses 12...

Among the optical structures investigated for optical sensing purpose, a significant amount of research has been conducted on photonic crystal based sensors. A particular advantage of photonic crystal based sensors is that they show superior sensitivity for ultra-small volume sensing. In this study we investigate polarization changes in response to the changes in the cover index of magneto-opti...