Two Dimensional Photonic Filter with a Circular Resonant Cavity

2013 ◽  
Vol 712-715 ◽  
pp. 1751-1754
Author(s):  
Zhao Xia Wu ◽  
Yuan Long Shao ◽  
Wen Chao Li ◽  
Er Dan Gu
Keyword(s):  
Dielectric Constant ◽  
Resonant Cavity ◽  
Fdtd Method ◽  
Circular Ring ◽  
Two Dimensional ◽  
Transmission Characteristics ◽  
New Type ◽  
Micro Cavity ◽  
The Impact ◽  
Difference Time

A new type of the two dimensional photonic filter which includes two in-line waveguides and a circular ring resonant cavity is presented in this paper. By using Finite Difference Time Domain (FDTD) method, we calculated and demonstrated the broadband frequency response of the filter and analyzed the impact of changing the dielectric constant of the inner rods on the transmission characteristics of the filter. Compared with the transmission characteristics of a micro-cavity,our numerical results show that such a filter can transmit multiple narrowband signals simultaneously. The number of the passbands of the filter increases with the rings of inner dielectric rods in the cavity. The center wavelength of the passbands can be tuned by adjusting the dielectric constant of the whole rods and inner rods without changing the size of the cavity..

Investigation of Contact Conditions During Stamping of a Thin Plate

2020 ◽  
Author(s):  
Harshal Y. Shahare ◽  
Rohan Rajput ◽  
Puneet Tandon
Keyword(s):  
Wave Propagation ◽  
Material Properties ◽  
High Speed ◽  
Fdtd Method ◽  
Propagation Model ◽  
Transmitted Wave ◽  
Two Dimensional ◽  
Contact Conditions ◽  
Simulation Based ◽  
Difference Time

Abstract Stamping is one of the most used manufacturing processes, where real-time monitoring is quite difficult due to high speed of the mechanical press, which leads to deterioration of the accuracy of the products In the present work, a method is developed to model elastic waves propagation in solids to measure contact conditions between die and workpiece during stamping. A two-dimensional model is developed that reduces the wave propagation equations to two-dimensional equations. To simulate the wave propagation inside the die-workpiece model, the finite difference time domain (FDTD) method and modified Yee algorithm has been employed. The numerical stability of the wave propagation model is achieved through courant stability condition, i.e., Courant-Friedrichs-Lewy (CFL) number. Two cases, i.e., flat die-workpiece interface and inclined die-workpiece interface, are investigated in the present work. The elastic wave propagation is simulated with a two-dimension (2D) model of the die and workpiece using reflecting boundary conditions for different material properties. The experimental and simulation-based results of reflected and transmitted wave characteristics are compared for different materials in terms of reflected and transmitted wave height ratio and material properties such as acoustic impedance. It is found that the numerical simulation results are in good agreement with the experimental results.

Contribution of Strain and Elasto-Optical Effect to Resonant Mode in the Two-Dimensional Photonic Crystals Force Sensor

2011 ◽  
Vol 216 ◽  
pp. 148-152 ◽  
Author(s):  
Yan Li ◽  
Hai Wei Fu ◽  
Xiao Li Li ◽  
Min Shao
Keyword(s):  
Finite Difference Time Domain ◽  
Resonant Cavity ◽  
Force Sensor ◽  
Resonant Mode ◽  
Resonant Wavelength ◽  
Two Dimensional ◽  
Optical Effect ◽  
Sensor Model ◽  
Two Dimensional Photonic Crystal ◽  
Difference Time

The resonant wavelength of the two-dimensional photonic crystal force sensor model changing with normal stress along y direction is calculated by finite-difference time-domain method. The result shows that the variation of the size and shape of the resonant cavity has a main contribution to the variation of the resonant wavelength. The elasto-optical effect of GaAs medium can not obviously change the wavelength of the resonant cavity below score of megapascal.

Corrugated SNOM probe with enhanced energy throughput

2008 ◽  
Vol 16 (4) ◽  
Author(s):  
T. Antosiewicz ◽  
T. Szoplik
Keyword(s):  
Near Field ◽  
Three Dimensional ◽  
Energy Output ◽  
Dipolar Field ◽  
Two Dimensional ◽  
The Core ◽  
Dimensional Approximation ◽  
New Type ◽  
Difference Time ◽  
Main Factor

AbstractIn a previous paper we proposed a modification of metal-coated tapered-fibre aperture probes for scanning near-field optical microscopes (SNOMs). The modification consists in radial corrugations of the metal-dielectric interface oriented inward the core. Their purpose is to facilitate the excitation of surface plasmons, which increase the transport of energy beyond the cut-off diameter and radiate a quasi-dipolar field from the probe output rim. An increase in energy output allows for reduction of the apex diameter, which is the main factor determining the resolution of the microscope. In two-dimensional finite-difference time-domain (FDTD) simulations we analyse the performance of the new type of SNOM probe. We admit, however, that the two-dimensional approximation gives better results than expected from exact three-dimensional ones. Nevertheless, optimisation of enhanced energy throughput in corrugated probes should lead to at least twice better resolution with the same sensitivity of detectors available nowadays.

Effect of Metal Intercalating on Transmission Characteristics of One-Dimensional Photonic Crystal

2011 ◽  
Vol 418-420 ◽  
pp. 679-683
Author(s):  
Bei Jia He ◽  
Xin Yi Chen ◽  
Jian Bo Wang ◽  
Jun Lu ◽  
Jian Chang ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Plasma Frequency ◽  
Fdtd Method ◽  
Transmission Characteristics ◽  
Material Characteristic ◽  
One Dimensional ◽  
Dimensional Photonic Crystal ◽  
Simulation Results ◽  
The One ◽  
Difference Time

To expand the bandgap's width of the one-dimensional photonic crystal, a crystal named SiO2/Metal/MgF2 is formed by joining some metals into the crystal SiO2/MgF2. Furthermore the Finite Difference Time Domain (FDTD) method is used to explore the metals' influence on the crystal's transmission characteristics. The simulation results show that the metals joined could expand the width of the one-dimensional photonic crystal's bandgap effectively and the bandgap's width increases when the metals' thickness increases. Meanwhile the bandgap's characteristic is affected by the metals' material-characteristic. The higher the plasma frequency is, the wider the bandgap's width will be and the more the number of the bandgaps will be. On the other hand, the metals' damping frequency has no significant effect on the bandgap, but would make the bandgap-edge's transmittance decrease slightly.

Design Two Dimensional Nanocavity Photonic Crystal Biosensor Detection in Malaria

2018 ◽  
Vol 6 (6) ◽  
pp. 16 ◽  
Author(s):  
Varsha Sharma ◽  
Vijay Laxmi Kalyani
Keyword(s):  
Photonic Crystal ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Fdtd Method ◽  
Expansion Method ◽  
Two Dimensional ◽  
Plane Wave Expansion ◽  
Plane Wave Expansion Method ◽  
Output Terminal ◽  
Difference Time

In this paper we design a two dimensional (2-D) photonic crystal based biosensor implemented by linear waveguide and nanocavity detection in malaria. The bio molecules such as a red blood cell, infected red blood cell, trapped inside the nanocavity cause transmission shift at the output terminal.  The sensing mechanism of biosensor is change in refractive index of analytes. The layout biosensor is consists a linear waveguide with a nanocavity in square symmetry For the proposed photonic based biosensor, the band gap from 2210nm to 1420 nm and input wavelength of 1550nm are used in this design. The simulation results have analysed by using the finite difference time domain (FDTD) method, bandgap calculation is performed using plane wave expansion method.

A New Two-Sided Coupling Channel Drop Filter Based on a Two-Dimensional Photonic Crystal

2013 ◽  
Vol 760-762 ◽  
pp. 417-420
Author(s):  
Xiang Nan Zhang ◽  
Gui Qiang Liu ◽  
Ying Hu ◽  
Zheng Jie Cai ◽  
Yuan Hao Chen
Keyword(s):  
Photonic Crystal ◽  
Integrated Circuits ◽  
Wavelength Division Multiplexing ◽  
Communication Systems ◽  
Light Propagation ◽  
Fdtd Method ◽  
Two Dimensional ◽  
Perfectly Matched Layers ◽  
Coupling Channel ◽  
Micro Cavity

We design a new two-sided coupling channel drop filter (CDF) based on a two-dimensional (2D) photonic crystal (PC). Three channels formed by line defects for light propagation, two L4 resonators positioned at both sides of the input waveguide for light coupling, and one point defect micro-cavity in the bus waveguide for wavelength-selective reflection are introduced into the PC structure. The optical characteristics of this proposed structure are calculated by finite-difference time-domain (FDTD) method combined with the perfectly matched layers (PMLs) as the boundary conditions. Three wavelengths centered at 1550, 1575 and 1610 nm within the limit of communication windows are successfully separated in three channels by adjusting the size of coupling rods and the positions of L4 resonators and micro-cavity. High transmission efficiency and more than 20 nm channel spacing are achieved. These demonstrate that our proposed structure is suitable for photonic integrated circuits (PICs) and coarse wavelength division multiplexing (WDM) optical communication systems.

Photonic Crystal Cavity with L3-Defect for Resonant Optical Filtering

Frequenz ◽  
2014 ◽  
Vol 68 (11-12) ◽  
Author(s):  
Mahdi Zavvari ◽  
Farhad Mehdizadeh
Keyword(s):  
Photonic Crystal ◽  
Resonant Cavity ◽  
Optical Filter ◽  
Transmission Efficiency ◽  
Plane Wave Expansion ◽  
Optical Filtering ◽  
Input And Output ◽  
The Impact ◽  
Difference Time ◽  
Novel Design

AbstractA novel design of optical filter based on photonic crystal structure is proposed in this paper. For designing the proposed filter we introduce an L3 resonant cavity between the input and output waveguides. We study the impact of different parameters on the filtering behavior of the structure using plane wave expansion and finite difference time domain methods. The initial form of this filter is capable of selecting the optical waves at λ = 1557.8 nm and the transmission efficiency of the filter is obtained about 84%. The total footprint of the filter is less than 205 μm

Characteristics of 2D Cylindrical Photonic Crystals Band Gap with Square Lattice

2013 ◽  
Vol 712-715 ◽  
pp. 302-305
Author(s):  
Zhao Xia Wu ◽  
Wen Chao Li ◽  
Er Dan Gu ◽  
Li Fu Wang
Keyword(s):  
Dielectric Constant ◽  
Photonic Crystals ◽  
Band Gap ◽  
Photonic Band Gap ◽  
Fdtd Method ◽  
Dielectric Constants ◽  
Square Lattice ◽  
The Difference ◽  
Difference Time ◽  
Photonic Band

The structure of two-dimensional (2D) photonic crystals (PCs) with square lattice is proposed in this paper, and researches on characteristics of photonic band gap (PBG) are conducted using finite difference time domain (FDTD) method, then the effects of the dielectric constant and the radius of dielectric rods on band gap are analysed, dielectric rods in air (rods/air). The research results indicate that in the case of TE and TM polarization mode, the difference value of dielectric constant of medium and dielectric rods affects forming PBG.The band gap broadens with the difference value increasing. Whats more, the complete band gap (CBG) appears in range of large rods radius structure when dielectric constants of rods are smaller than that of medium.

scholarly journals Electromagnetic Imaging of Two-Dimensional Geometries by Multipulse Interference Using the Inverse FDTD Method

2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
Naoki Okada ◽  
James B. Cole
Keyword(s):  
Fdtd Method ◽  
Simple Calculation ◽  
The Body ◽  
Two Dimensional ◽  
Multiple Objects ◽  
Incident Wavelength ◽  
Electromagnetic Imaging ◽  
Imaging Results ◽  
Phase Interference ◽  
Difference Time

The size, shape, and location of unknown objects in the ground and in the body can be estimated by an electromagnetic imaging technique. An imaging approach to clear detection of two-dimensional geometries is proposed in this paper. Based on the inverse finite-difference time-domain (FDTD) method, a phase interference technique using multidirectional pulses is employed. The advantage of the proposed method is that it can clearly reconstruct the geometry in a simple calculation. Sample imaging results are demonstrated. The analysis of the FDTD results shows that the detectable object size is limited by the incident wavelength and the measurement spacing and illustrates the detectability of multiple objects.

Sign in / Sign up

Export Citation Format

Share Document