scholarly journals Cuticle network and orientation preference of photonic crystals in the scales of the weevil Lamprocyphus augustus

2018 ◽  
Vol 15 (145) ◽  
pp. 20180360 ◽  
Author(s):  
R. Ebihara ◽  
H. Hashimoto ◽  
J. Kano ◽  
T. Fujii ◽  
S. Yoshioka
Keyword(s):  
Crystal Structure ◽  
Photonic Crystal ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Three Dimensional ◽  
Unit Cell ◽  
Photonic Crystal Structure ◽  
Dimensional Structure ◽  
Microscopy Imaging ◽  
Photonic Band

This paper reports the structural and optical investigations of the structural colour of the weevil Lamprocyphus augustus . The photonic crystal structure within the weevil's scales was investigated using sequential focused ion-beam milling and scanning electron microscopy imaging. We carefully analysed the reconstructed three-dimensional structure to determine the unit cell of the photonic crystal. It was found that the cuticle network of the cubic unit cell perfectly matches the previously reported diamond-based network. However, different results were obtained for the crystal orientations of the small crystal domains that comprise the entire photonic crystal structure in the scales: <111> directions are highly preferred along the surface normal of the scale. This finding explains the fact that the scale is almost uniformly coloured despite the multi-domain structure. It is confirmed experimentally and theoretically that the wavelength range of the reflection band corresponds to the gap of the photonic band.

Fabrication and simulation of 1540-nm transmission by 532-nm excitation in photonic crystal of Er:ZnO film

2017 ◽  
Vol 6 (6) ◽  
pp. 497-503 ◽  
Author(s):  
Ranran Fan ◽  
Fei Lu ◽  
Kaikai Li
Keyword(s):  
Crystal Structure ◽  
Photonic Crystal ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Single Mode ◽  
Photonic Devices ◽  
Photonic Crystal Structure ◽  
Ion Beam Etching ◽  
Er Doped ◽  
532 Nm

AbstractErbium (Er)-doped ZnO thin film is fabricated on sapphire substrate by radio frequency magnetron sputtering technology. The as-deposited Er:ZnO film has a good film quality and exhibits excellent single-mode waveguide characteristic. A photonic crystal structure in the Er:ZnO film is fabricated by focused-ion-beam etching. When the film is stimulated by a 532 nm laser, photoluminescence (PL) at 1540 nm can be excited. Simulation results show that the propagation of Er-related emission of 1540 nm will be well restricted along a certain direction in the photonic crystal structure. It provides a novel way to control and confine the transmission of light in ZnO waveguide and will be applicable for the application of Er:ZnO photonic devices.

scholarly journals Site Specific Three-dimensional Structural Analysis in Tissues and Cells Using Automated DualBeam Slice &View

2007 ◽  
Vol 15 (2) ◽  
pp. 26-31 ◽  
Author(s):  
Ben Lich
Keyword(s):  
Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Three Dimensional ◽  
Surface Region ◽  
Dimensional Structure ◽  
Near Surface ◽  
Imaging Capability ◽  
Fluorescent Markers ◽  
Confocal And Electron Microscopy

DualBeam instruments that combine the imaging capability of scanning electron microscopy (SEM) with the cutting and deposition capability of a focused ion beam (FIB) provide biologists with a powerful tool for investigating three-dimensional structure with nanoscale (1 nm-100 nm) resolution. Ever since Van Leeuwenhoek used the first microscope to describe bacteria more than 300 years ago, microscopy has played a central role in scientists' efforts to understand biological systems. Light microscopy is generally limited to a useful resolution of about a micrometer. More recently the use of confocal and electron microscopy has enabled investigations at higher resolution. Used with fluorescent markers, confocal microscopy can detect and localize molecular scale features, but its imaging resolution is still limited. SEM is capable of nanometer resolution, but is limited to the near surface region of the sample.

Three-dimensional structure analysis of melanocytes and keratinocytes in senile lentigo

Microscopy ◽  
2020 ◽  
Author(s):  
Yuki Mizutani ◽  
Mika Yamashita ◽  
Rie Hashimoto ◽  
Toru Atsugi ◽  
Akemi Ryu ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Normal Skin ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Confocal Laser ◽  
Scanning Electron Micrographs ◽  
Large Numbers ◽  
Dimensional Reconstruction

Abstract Senile lentigo or age spots are hyperpigmented macules of skin that commonly develop following long-term exposure to ultraviolet radiation. This condition is caused by accumulation of large numbers of melanosomes (melanin granules) produced by melanocytes within neighboring keratinocytes. However, there is still no consensus regarding the melanosome transfer mechanism in senile lentigo. To date, most pathohistological studies of skin have been two-dimensional and do not provide detailed data on the complex interactions of the melanocyte–keratinocyte network involved in melanosome transfer. We performed a three-dimensional reconstruction of the epidermal microstructure in senile lentigo using three different microscopic modalities to visualize the topological melanocyte–keratinocyte relationship and melanosome distribution. Confocal laser microscopy images showed that melanocyte dendritic processes are more frequently branched and elongated in senile lentigo skin than in normal skin. Serial transmission electron micrographs showed that dendritic processes extend into intercellular spaces between keratinocytes. Focused ion beam-scanning electron micrographs showed that dendritic processes in senile lentigo encircle adjacent keratinocytes and accumulate large numbers of melanosomes. Moreover, melanosomes transferred to keratinocytes are present not only in the supranuclear area but throughout the perinuclear area except on the basal side. The use of these different microscopic methods helped to elucidate the three-dimensional morphology and topology of melanocytes and keratinocytes in senile lentigo. We show that the localization of melanosomes in dendritic processes to the region encircling recipient keratinocytes contributes to efficient melanosome transfer in senile lentigo.

X-ray nanotomography and focused-ion-beam sectioning for quantitative three-dimensional analysis of nanocomposites

2016 ◽  
Vol 23 (4) ◽  
pp. 990-996 ◽  
Author(s):  
Christopher E. Shuck ◽  
Mathew Frazee ◽  
Andrew Gillman ◽  
Matthew T. Beason ◽  
Ibrahim Emre Gunduz ◽  
...  
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Three Dimensional ◽  
Nondestructive Method ◽  
Material Behavior ◽  
Dimensional Structure ◽  
X Ray ◽  
The Monte Carlo Method ◽  
Micrometer Size

Knowing the relationship between three-dimensional structure and properties is paramount for complete understanding of material behavior. In this work, the internal nanostructure of micrometer-size (∼10 µm) composite Ni/Al particles was analyzed using two different approaches. The first technique, synchrotron-based X-ray nanotomography, is a nondestructive method that can attain resolutions of tens of nanometers. The second is a destructive technique with sub-nanometer resolution utilizing scanning electron microscopy combined with an ion beam and `slice and view' analysis, where the sample is repeatedly milled and imaged. The obtained results suggest that both techniques allow for an accurate characterization of the larger-scale structures, while differences exist in the characterization of the smallest features. Using the Monte Carlo method, the effective resolution of the X-ray nanotomography technique was determined to be ∼48 nm, while focused-ion-beam sectioning with `slice and view' analysis was ∼5 nm.

scholarly journals Photonic band in quasi-fractal photonic crystal structure including idealized metal

2004 ◽  
Vol 53 (9) ◽  
pp. 3205
Author(s):  
Li Yan ◽  
Zheng Rui-Sheng ◽  
Feng Yu-Chun ◽  
Niu Han-Ben
Keyword(s):  
Crystal Structure ◽  
Photonic Crystal ◽  
Photonic Crystal Structure ◽  
Photonic Band
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