Dispersion characteristics of two types of two-dimension dielectric plasma photonic crystal are studied based on modified plane wave method. Firstly, the eigenvalue equations of TM mode of type-1 and type-2 structures are derived respectively; their dispersion curves are confirmed by the software simulation. Secondly, the influences of normalized plasma frequency, filling factor and relative dielectric constant on photonic band gap, and relative photonic band gap width are analyzed respectively, and some corresponding physical explanations are also given. These results would provide theoretical instructions for designing new photonic crystal devices using plasma- dielectric structure.

https://www.jpier.org/PIER/pier91/20.09022605.pdf

Modified Plane Wave Method Analysis of Dielectric Plasma Photonic Crystal

Calculation of the emission power distribution of microstructured OLEDs using the reciprocity theorem

We present a light emitting diode with a two-dimensional photonic crystal structure prepared by interference lithography at the light emitting diode surface. The emission maximum is at 850 nm. The two-dimensional photonic crystal structure enhanced the light extraction efficiency by a factor of 1.39. The photonic crystal light emitting diode surface morphology was analyzed by atomic force microscopy. The enhanced extraction efficiency of the photonic crystal diode was documented from L ( I ) dependencies and was confirmed by near-field studies.

Light extraction from a light emitting diode with photonic structure in the surface layer investigated by NSOM

In this paper, we use the Bloch theorem and transfer matrix method to calculate the dispersion relation of a ternary 1D photonic crystal with left-handed materials. Then, we obtain the total omnidirectional re∞ection band gaps of this structure. We demonstrate that the omnidirectional re∞ected frequency bands are enlarged in comparison with ordinary materials with positive index of refraction.

Photonic Band Structures and Enhancement of Omnidirectional Reflection Bands by Using a Ternary 1D Photonic Crystal Including Left-Handed Materials

dimension flnite-difierence time-domain (FDTD) method is used to simulate the enhanced blue light emission of gallium nitride light emitting diode (GaN-LED) using the surface-plasmons (SPs) cou- pling with the quantum wells. The numerical simulation results demon- strate that when the silver fllm is coated on GaN-LED, the excited SPs play a key role in the enhanced blue light emission, and the en- hancement depends on the geometries of GaN-LED and silver fllm. An enhancement factor is given to describe the enhancement efiect of light emission. By changing the structure parameters of GaN-LED and sil- ver fllm, the enhanced peak of the light emission in the visible region can be controlled. Under the optimal parameters, about 17 times en- hancement at 460nm can be obtained, and the enhancement efiect is evidently demonstrated by the SPs fleld distribution.

/pdf/enhancement-of-blue-light-emission-using-surface-plasmons-3cme1iwzxj.pdf

Enhancement of blue light emission using surface plasmons coupling with quantum wells

Light extraction efficiency of light-emitting diodes (LEDs) based on various photonic crystal (PhC) structures is investigated in this study. By using the plane wave method and the finite element method, the influence of several factors on the enhancement of light extraction is discussed, including lattice type, the density of states from a photonic band diagram, the ratio of cylinder radius and lattice constant, and the thickness of a PHC pattern. Some rules are given for the practical implementation of an optimized PhC-based LED with higher light extraction efficiency. In the simulation results, the maximum enhancement of the extraction efficiency could be by a factor of approximately 2.8 for the optimized Archimedean tiling pattern in the LED device emitting at the center wavelength of 530 nm. However, with the use of optimized PhC structures, the square and triangular lattices reveal enhancements of ∼ 1.7 and ∼ 1.5, respectively. The extraction efficiency of the Archimedean PhC LED is much greater than that of the regular lattice PhC LED.

/pdf/design-and-modeling-for-enhancement-of-light-extraction-in-3dl7nodh3a.pdf

and Ching-Cheng Wang

Papers

Design and modeling for enhancement of light extraction in light-emitting diodes with Archimedean lattice photonic crystals