Rotational Invariance of the Effective Refractive Index in Photonic Crystals

2012 ◽  
Vol 24 (22) ◽  
pp. 2070-2073
Author(s):  
Ting-Hang Pei ◽  
Yang-Tung Huang
Keyword(s):  
Refractive Index ◽  
Photonic Crystals ◽  
Effective Refractive Index ◽  
Rotational Invariance

scholarly journals Titania Photonic Crystals with Precise Photonic Band Gap Position via Anodizing with Voltage versus Optical Path Length Modulation

Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 651 ◽  
Author(s):  
Ermolaev ◽  
Kushnir ◽  
Sapoletova ◽  
Napolskii
Keyword(s):  
Refractive Index ◽  
Photonic Crystals ◽  
Band Gap ◽  
Titanium Oxide ◽  
Effective Refractive Index ◽  
Photonic Band Gap ◽  
Voltage Versus ◽  
Research Attention ◽  
Anodic Titanium Oxide ◽  
Photonic Band

Photonic crystals based on titanium oxide are promising for optoelectronic applications, for example as components of solar cells and photodetectors. These materials attract great research attention because of the high refractive index of TiO2. One of the promising routes to prepare photonic crystals based on titanium oxide is titanium anodizing at periodically changing voltage or current. However, precise control of the photonic band gap position in anodic titania films is a challenge. To solve this problem, systematic data on the effective refractive index of the porous anodic titanium oxide are required. In this research, we determine quantitatively the dependence of the effective refractive index of porous anodic titanium oxide on the anodizing regime and develop a model which allows one to predict and, therefore, control photonic band gap position in the visible spectrum range with an accuracy better than 98.5%. The prospects of anodic titania photonic crystals implementation as refractive index sensors are demonstrated.

Large area light propagation in quasi-zero average refractive index materials

2009 ◽  
Vol 1182 ◽  
Author(s):  
Principia Dardano ◽  
Vito Mocella ◽  
Stefano Cabrini ◽  
Allan S. Chang ◽  
Luigi Moretti ◽  
...  
Keyword(s):  
Refractive Index ◽  
Photonic Crystals ◽  
Effective Refractive Index ◽  
Light Propagation ◽  
Near Infrared ◽  
Experimental Results ◽  
Infrared Light ◽  
Large Area ◽  
Near Infrared Light ◽  
Average Refractive Index

AbstractIn this paper the experimental results show near-infrared light collimation through large area (2 x 2 mm) nanopatterned material with refractive index quasi-zero on the average. This quasi-zero refractive index is obtained alternating photonic crystals strips with effective refractive index neff = –1 and air strips (n = 1). Layers optically annihilate each other, verifying the optical antimatter concept theoretically proposed by Pendry et al [J. Phys.: Condens. Matter 15, 6345 (2003)].

scholarly journals Synthesis and properties of SiO2 photonic crystals modified by DNA

2020 ◽  
Keyword(s):  
Refractive Index ◽  
Photonic Crystal ◽  
Photonic Crystals ◽  
Electric Field ◽  
Band Gap ◽  
Effective Refractive Index ◽  
Fdtd Method ◽  
Optical Parameters ◽  
Globular Photonic Crystal ◽  
The Creation

Background: Photonic crystals are structures characterized by periodic modulations of the refractive index with a period commensurate with the wavelength. This periodicity is associated with the existence of a complete band gap in the spectrum of the electromagnetic states of the crystal. The stop zone is called the band gap for the highlighted direction in the crystal. Globular photonic crystals are called three-dimensional photonic crystals, which consist of the same diameter globules. The pores between the globules in the opal allow one to change the refractive index and optical contrast of the material. The task of controlling the stop-zone frequency limits of a globular photonic crystal without changing its physical structure is of practical interest. The easiest way to control the stop-zone parameters is to fill the pores of the photonic crystals with materials with different refractive indices, for example, DNA. Control of the optical parameters of a globular photonic crystal can be used for the creation of optical detectors, sensors, test systems, a quantum biocomputer as well as analyzing and studying a conformational state of DNA. Objectives: the creation of SiO2 globular photonic crystals modified by DNA and studying of the influence of DNA on their optical properties. Materials and Methods: Ethyl alcohol, distilled water, ammonium hydroxide, tetraethoxysilane and DNA were used to synthesize SiO2 photonic crystals. Aqueous DNA solution was used to infiltrate the photonic crystals. We used a visible range spectroscopy for optical experiments and a finite-difference time-domain (FDTD) method for numerical calculations. Results: SiO2 globular photonic crystals modified by DNA were synthesized with 195 nm globules. The reflection spectra of the obtained photonic crystals were measured. A red-shift of the stop-zone maximum after the infiltration of photonic crystals with DNA molecules was found. The electric field distribution was calculated for the photonic crystal with 200 nm globules. Conclusions: FDTD calculations in the linear mode show that the presence of point defects in the structure of the photonic crystal influences the amplification of the local electric field in the interglobular space of the photonic crystal, which houses the DNA molecule at infiltration. The DNA infiltration into the pores of a photonic crystal changes the effective refractive index of the system by 5.99%. Synthesis SiO2 photonic crystals with DNA leads to the formation of a more ordered structure at the macro levels. Thus, DNA serves as a template-like structure for photonic crystals to be assembled on. In this case, the effective refractive index of the system increases by 6.01%.

Effects of geometric and refractive index disorder on wave propagation in two-dimensional photonic crystals

2000 ◽  
Vol 62 (4) ◽  
pp. 5711-5720 ◽  
Author(s):  
A. A. Asatryan ◽  
P. A. Robinson ◽  
L. C. Botten ◽  
R. C. McPhedran ◽  
N. A. Nicorovici ◽  
...  
Keyword(s):  
Refractive Index ◽  
Wave Propagation ◽  
Photonic Crystals ◽  
Two Dimensional
Sign in / Sign up

Export Citation Format

Share Document