scholarly journals Electromagnetic characterization of millimetre-scale replicas of the gyroid photonic crystal found in the butterfly Parides sesostris

2012 ◽  
Vol 2 (5) ◽  
pp. 645-650 ◽  
Author(s):  
C. Pouya ◽  
P. Vukusic
Keyword(s):  
Photonic Crystal ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Normal Incidence ◽  
Electromagnetic Response ◽  
Transmission Minimum ◽  
Index Contrast ◽  
Material Volume ◽  
Microwave Regime

We have used three-dimensional stereolithography to synthetically replicate the gyroid photonic crystal (PC) structure that occurs naturally in the butterfly Parides sesostris . We have experimentally characterized the transmission response of this structure in the microwave regime at two azimuthal angles ( ϕ ) over a comprehensive range of polar angles ( θ ). We have modelled its electromagnetic response using the finite-element method (FEM) and found excellent agreement with experimental data. Both theory and experiment show a single relatively broad transmission minimum at normal incidence ( θ = 0°) that comprises several narrow band resonances which separate into clearly identifiable stop-bands at higher polar angles. We have identified the specific effective geometric planes within the crystal, and their associated periodicities that give rise to each of these stop-bands. Through extensive theoretical FEM modelling of the gyroid PC structure, using varying filling fractions of material and air, we have shown that a gyroid PC with material volume fraction of 40 per cent is appropriate for optimizing the reflected bandwidth at normal incidence (for a refractive index contrast of 1.56). This is the same gyroid PC material volume fraction used by the butterfly P. sesostris itself to produce its green structurally coloured appearance. This infers further optimization of this biological PC beyond that of its lattice constant alone.

Transmission Characterization of Drilled Alternating-Layer Three-Dimensional Photonic Crystals

2001 ◽  
Vol 692 ◽  
Author(s):  
Eiichi Kuramochi ◽  
Masaya Notomi ◽  
Itaru Yokohama ◽  
Jun-ichi Takahashi ◽  
Chiharu Takahashi ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Cyclotron Resonance ◽  
Electron Cyclotron Resonance ◽  
Light Transmission ◽  
Photonic Band Gap ◽  
Three Dimensional ◽  
Dielectric Films ◽  
Transmission Minimum ◽  
Photonic Band

AbstractWe propose a new three-dimensional photonic crystal structure or drilled alternating-layer photonic crystal (DALPC), which can be fabricated by a combination of the deposition of alternating layers of dielectric films and one-time dry etching. Our band calculation predicts that the DALPC has a photonic band gap (PBG) in all directions. We fabricated a Si/SiO2DALPC by electron beam lithography, bias sputtering, and fluoride-gas electron cyclotron resonance etching. We measured the light transmission of the DALPC sample in both the in-plane and vertical directions. We observed a transmission minimum around the 1.4-μm-wavelength for all measured directions and TE/TM polarizations, which demonstrated a potential of the DALPC as a three-dimensional PBG material.

Transmission Characterization of Drilled Alternating-Layer Three-Dimensional Photonic Crystals

2001 ◽  
Vol 694 ◽  
Author(s):  
Eiichi Kuramochi ◽  
Masaya Notomi ◽  
Itaru Yokohama ◽  
Jun-ichi Takahashi ◽  
Chiharu Takahashi ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Cyclotron Resonance ◽  
Electron Cyclotron Resonance ◽  
Light Transmission ◽  
Photonic Band Gap ◽  
Three Dimensional ◽  
Dielectric Films ◽  
Transmission Minimum ◽  
Photonic Band

AbstractWe propose a new three-dimensional photonic crystal structure or drilled alternating-layer photonic crystal (DALPC), which can be fabricated by a combination of the deposition of alternating layers of dielectric films and one-time dry etching. Our band calculation predicts that the DALPC has a photonic band gap (PBG) in all directions. We fabricated a Si/SiO2 DALPC by electron beam lithography, bias sputtering, and fluoride-gas electron cyclotron resonance etching. We measured the light transmission of the DALPC sample in both the in-plane and vertical directions. We observed a transmission minimum around the 1.4-µm-wavelength for all measured directions and TE/TM polarizations, which demonstrated a potential of the DALPC as a three-dimensional PBG material.

Three-Dimensional Characterization of the Microstructure of Bioglass/Polyethylene Composite by X-Ray Microtomography

2007 ◽  
Vol 330-332 ◽  
pp. 503-506
Author(s):  
Xiao Wei Fu ◽  
Jie Huang ◽  
E.S. Thian ◽  
Serena Best ◽  
William Bonfield
Keyword(s):  
Spatial Distribution ◽  
Volume Fraction ◽  
Three Dimensional ◽  
X Ray ◽  
Polyethylene Composite ◽  
Bioactive Properties ◽  
Recent Developments ◽  
3D Information

A Bioglass® reinforced polyethylene (Bioglass®/polyethylene) composite has been prepared, which combines the high bioactivity of Bioglass® and the toughness of polyethylene. The spatial distribution of Bioglass® particles within the composite is important for the performance of composites in-vivo. Recent developments in X-ray microtomography (XμT) have made it possible to visualize internal and microstructural details with different X-ray absorbencies, nondestructively, and to acquire 3D information at high spatial resolution. In this study, the volume fraction and 3D spatial distribution of Bioglass® particles has been acquired quantitatively by XμT. The information obtained provides a foundation for understanding the mechanical and bioactive properties of the Bioglass®/polyethylene composites.

scholarly journals Progress on numerical simulation of nanofluids: impact of an isothermal spherical partition on the mixed convection of nanofluids within cubic enclosures

2020 ◽  
Vol 307 ◽  
pp. 01016
Author(s):  
A. BOUTRA ◽  
K. RAGUI ◽  
N. LABSI ◽  
Y.K. BENKAHLA ◽  
R BENNACER
Keyword(s):  
Lattice Boltzmann ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Numerical Code ◽  
Three Dimensional Flow ◽  
Boltzmann Method ◽  
Do So

The main objective of our work is to light out the three-dimensional flow of an Ag-water nanofluid within a lid-driven cubical space which equipped with a spherical heater into its center. Due to its crucial role in the characterization of the main transfer within such configurations, impact of some parameters is widely inspected. It consists the Richardson value (0,05 to 50), the solid volume fraction (0% to 10%), as well as the heater geometry (10% ≤ d ≤ 25%). To do so, a numerical code based on the Lattice-Boltzmann method, coupled with a finite difference one, is used. The latter has been validated after comparison between the present results and those of the literature. It is to note that the three dimensions D3Q19 model is adopted based on a cubic Lattice, where each pattern of the latter is characterized by nineteen discrete speeds.

scholarly journals Discovery of I-WP minimal-surface-based photonic crystal in the scale of a longhorn beetle

2021 ◽  
Vol 18 (184) ◽  
Author(s):  
Yuka Kobayashi ◽  
Ryosuke Ohnuki ◽  
Shinya Yoshioka
Keyword(s):  
Photonic Crystal ◽  
Minimal Surface ◽  
Volume Fraction ◽  
Domain Boundary ◽  
Three Dimensional ◽  
Structural Features ◽  
Diamond Surfaces ◽  
Periodic Minimal Surface ◽  
Longhorn Beetle ◽  
Triply Periodic Minimal Surface

The structural colours of certain insects are produced by three-dimensional periodic cuticle networks. The topology of the cuticle network is known to be based on the mathematically well-defined triply periodic minimal surface. In this paper, we report the discovery of an I-WP minimal-surface-based photonic crystal on the scale of a longhorn beetle. In contrast to gyroid or diamond surfaces, which are found in butterfly and weevil scales, respectively, the I-WP surface is an unbalanced minimal surface, wherein two subspaces separated by the surface are different in terms of shape and volume fraction. Furthermore, adjacent photonic crystal domains were observed to share a particular crystal plane as their domain boundary, indicating that they were developed as twin crystals. These structural features pose certain new questions regarding the development of biological photonic crystals. We also performed an optical analysis of the structural colour of the longhorn beetle and successfully explained the wavelength of reflection by the photonic bandgap of the I-WP photonic crystal.

Characterization of the mineral phases of the iron ore pellet via 3D reconstruction using serial sectioning

2019 ◽  
Vol 116 (1) ◽  
pp. 117
Author(s):  
Wang Wei ◽  
Heng Zheng ◽  
Runsheng Xu ◽  
Fenglou Wu ◽  
Weilin Chen ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Iron Ore ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Serial Sectioning ◽  
3D Space ◽  
Binding Phase ◽  
Large Particles ◽  
Iron Ore Pellet

A new analysis method based on serial sectioning and three-dimensional (3D) reconstruction was developed for the quantification of minerals in an iron ore pellet. The morphology and spatial distribution of the minerals in 3D space were analysed via 3D reconstructed images of an iron ore pellet. The volume fraction of the minerals in the 3D image was also calculated based on the pixel points. The results showed that the morphology and spatial distributions of hematite, magnetite and silicate varied among different pellets as well as among different positions within the same pellet. Thick plate and interconnected hematite was observed in the outer area of the pellets, whereas the inner area of the pellets mainly contained small granular and independent hematite. The hematite grains in pellet 1 were small, whereas those in pellet 2 were relatively dense. Some of the magnetite in pellet 1 was in the form of dense blocks, whereas fewer blocks were found in pellet 2, where magnetite occurred mainly in chain form scattered within the large particles of hematite. The silicate in pellet 2 was dense, granular and smaller than that in pellet 1. The quantitative analysis results for the two kinds of pellets showed that pellet 2 contained more hematite. Moreover, pellet 2 contained less unoxidized magnetite than pellet 1. These results indicate that the main bonding phase in pellet 1 was magnetite, whereas the main binding phase in pellet 2 was hematite. The greater compressive strength of pellet 2 was strongly related to higher amount of hematite interconnections.

Topological Design of Three-Dimensional Microstructure Based on Homogenization Effective Method

2006 ◽  
Vol 532-533 ◽  
pp. 705-708
Author(s):  
Ke Peng Qiu ◽  
Wei Hong Zhang ◽  
Shi Ping Sun ◽  
Ji Hong Zhu
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Optimization Method ◽  
Homogenization Method ◽  
The Finite Element Method ◽  
Topological Design ◽  
Unit Cells ◽  
Material Volume ◽  
Specific Material ◽  
Optimal Material

Nowadays, the topology optimization method is extensively adopted for the design of material microstructures to achieve desired behaviors. The present work is concerned with the optimal design of the stiffness and thermal conductivity of 3D microstructure unit cells with the specific material volume fraction in conjunction with the homogenization method and the finite element method. Numerical examples are given to demonstrate that optimal material layouts are successfully achieved and the initial layout has a great effect on the optimal microstructure.

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