Design of Visible Broadband Metamaterial Absorber Based on Metal Nickel

Abstract In this paper,we have proposed a visible broadband metamaterial absorber based on metal Nickel. The metamaterial absorber (MA) is composed of three layers,which are Nickel-based pattern array on the top, silicon dioxide in the middle layer and Nickel film at the bottom. In the whole visible spectrum(380-780nm) of our study, the average absorption of the absorber is up to 95.60%. The absorption rates at 500nm and 637nm are 96.63% and 99.93%, respectively. Also, the proposed MA is insensitive of polarization in the whole visible regime. Later, the mechanism of the absorption and the influence of the structural parameters on the absorption spectrum are investigated. Strong electrical and magnetic resonance are related to the absorption peak at the resonant wavelength. The results show the resonant wavelength of 500nm is fixed and the resonant wavelength of 637nm can be tuned by the parameters.The proposed structure will have important application prospects in the field of solar cells.

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Broadband Solar Absorber Based on Square Ring cross Arrays of ZnS

Micromachines ◽

10.3390/mi12080909 ◽

2021 ◽

Vol 12 (8) ◽

pp. 909

Author(s):

Feng Xu ◽

Lixia Lin ◽

Jun Fang ◽

Mianli Huang ◽

Feng Wang ◽

...

Keyword(s):

Absorption Spectrum ◽

Visible Light ◽

Surface Plasmon ◽

Wide Spectrum ◽

Clean Energy ◽

Metamaterial Absorber ◽

Absorption Efficiency ◽

Plasmon Mode ◽

Solar Absorber ◽

Absorbing Material

Solar energy is an inexhaustible clean energy. However, how to improve the absorption efficiency in the visible band is a long-term problem for researchers. Therefore, an electromagnetic wave absorber with an ultra-long absorption spectrum has been widely considered by researchers of optoelectronic materials. A kind of absorbing material based on ZnS material is presented in this paper. Our purpose is for the absorber to achieve a good and wide spectrum of visible light absorption performance. In the wide spectrum band (553.0 THz–793.0 THz) of the absorption spectrum, the average absorption rate of the absorber is above 94%. Using surface plasmon resonance (SPR) and gap surface plasmon mode, the metamaterial absorber was studied in visible light. In particular, the absorber is insensitive to both electric and magnetic absorption. The absorber can operate in complex electromagnetic environments and at high temperatures. This is because the absorber is made of refractory metals. Finally, we discuss and analyze the influence of the parameters regulating the absorber on the absorber absorption efficiency. We have tried to explain why the absorber can produce wideband absorption.

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Comments on the Magnetic Resonance Absorption Spectrum of the F2-, Molecule-Ion in Single Crystals of LiF, NaF, and KF

physica status solidi (b) ◽

10.1002/pssb.2220820135 ◽

1977 ◽

Vol 82 (1) ◽

pp. 311-317 ◽

Cited By ~ 14

Author(s):

S. A. Marshall

Keyword(s):

Absorption Spectrum ◽

Magnetic Resonance ◽

Single Crystals ◽

Resonance Absorption

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Design and Analysis of a Triple-band Non-zonal Polarization Electromagnetic Metamaterial Absorber

Applied Computational Electromagnetics Society ◽

10.47037/2020.aces.j.360611 ◽

2021 ◽

Vol 36 (6) ◽

pp. 697-706

Author(s):

Han Wu ◽

Shijun Ji ◽

Ji Zhao ◽

Zhiyou Luo ◽

Handa Dai

Keyword(s):

Structural Parameters ◽

Surface Current ◽

Metamaterial Absorber ◽

Copper Plate ◽

Polarization Angle ◽

Absorption Mechanism ◽

Imaging Detector ◽

Polarization Insensitive ◽

Spectrum Imaging ◽

Triple Band

A facile design of a novel triple-band electromagnetic metamaterial absorber (MMA) with polarization insensitive property is proposed in this paper. Each unit of the MMA consists of upper copper resonator and bottom copper plate with middle dielectric FR-4 between them. The MMA performs three absorption peaks at 16.919 GHz, 21.084 GHz and 25.266 GHz with absorption rates 99.90%, 97.76% and 99.18%, respectively. The influence of the main structural parameters on the frequencies and absorption rates is analyzed. The absorption mechanism of the absorber is explained by electric field, magnetic field and surface current distributions, which is supported by the electromagnetic parameters, affected with magnetic resonance. The polarization-insensitivity of TE wave is verified by observing the effects of the polarization angle change from 0-90º. The MMA can be applied in radiation, spectrum imaging detector, electromagnetic wave modulator, and so on.

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Infrared Absorption Spectrum of Silicon Dioxide

Journal of the American Ceramic Society ◽

10.1111/j.1151-2916.1965.tb14680.x ◽

1965 ◽

Vol 48 (11) ◽

pp. 595-599 ◽

Cited By ~ 71

Author(s):

RINOUD HANNA

Keyword(s):

Absorption Spectrum ◽

Silicon Dioxide ◽

Infrared Absorption ◽

Infrared Absorption Spectrum

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Manipulation of Germanium Nanocrystals in a Tri-Layer Insulator Structure of a Metal-Insulator-Semiconductor Memory Device

MRS Proceedings ◽

10.1557/proc-728-s5.7 ◽

2002 ◽

Vol 728 ◽

Cited By ~ 1

Author(s):

L.W. Teo ◽

C.L. Heng ◽

V. Ho ◽

M. Tay ◽

W.K. Choi ◽

...

Keyword(s):

Silicon Dioxide ◽

Oxide Layer ◽

Layer Structure ◽

Charge Trapping ◽

Middle Layer ◽

Memory Device ◽

Metal Insulator ◽

Metal Insulator Semiconductor ◽

20 Nm ◽

Ge Nanocrystals

AbstractA metal-insulator-semiconductor (MIS) device that consists of germanium (Ge) nanocrystals embedded in a novel tri-layer insulator structure is proposed for memory applications [1]. The tri-layer structure comprises a thin (≈5nm) rapid thermal oxidation (RTO) silicon dioxide (SiO2) layer, a Ge+SiO2 middle layer (6 - 20 nm) deposited by RF co-sputtering technique and a RF-sputtered silicon dioxide capping layer. High-resolution transmission electron microscopy (HRTEM) results show that Ge nanocrystals of sizes ranging from 6 –20 nm were found after rapid thermal annealing of the trilayer structure at 1000°C for 300s. The electrical properties of these devices have been characterized using capacitance versus voltage (C-V) measurements. A significant hysteresis was observed in the C-V curves of these devices, indicating charge trapping in the composite insulator. Comparison with devices having similar tri-layer insulator structure, but with a pure sputtered oxide middle layer (i.e. minus the Ge nanocrystals), clearly indicated that the observed charge trapping is due to the presence of the Ge nanocrystals in the middle layer. The C-V measurements of devices without the capping SiO2 layer exhibited no significant hysteresis as compared to the embedded Ge nanocrystal tri-layer devices. The HRTEM micrographs showed that the presence of the capping oxide is critical in the formation of nanocrystals for this structure. By varying the thickness of the middle layer, it was found that the maximum nanocrystal size correlates well with the middle layer thickness. This indicates that the nanocrystals are well confined by the RTO oxide layer and the capping oxide layer. In addition, Ge nanocrystals formed using a thinner middle layer were found to be relatively uniform in size and distribution. This structure, therefore, offers a possibility of fabricating memory devices with controllable Ge nanocrystals size.

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Development of anatomically based customizable three-dimensional finite-element model of pelvic floor support system: POP-SIM1.0

Interface Focus ◽

10.1098/rsfs.2019.0022 ◽

2019 ◽

Vol 9 (4) ◽

pp. 20190022 ◽

Cited By ~ 2

Author(s):

Mark T. Gordon ◽

John O. L. DeLancey ◽

Aaron Renfroe ◽

Andrew Battles ◽

Luyun Chen

Keyword(s):

Finite Element ◽

Magnetic Resonance ◽

Pelvic Floor ◽

Support System ◽

Structural Parameters ◽

Vaginal Wall ◽

Abdominal Pressure ◽

Fe Model ◽

Vaginal Length ◽

Pelvic Floor Support

To develop an anatomically based customizable finite-element (FE) model of the pelvic floor support system to simulate pelvic organ prolapse (POP): POP-SIM1.0. This new simulation platform allows for the construction of an array of models that objectively represent the key anatomical and functional variation in women with and without prolapse to test pathomechanism hypotheses of the prolapse formation. POP-SIM1.0 consists of anatomically based FE models and a suite of Python-based tools developed to rapidly construct FE models by customizing the base model with desired structural parameters. Each model consists of anatomical structures from three support subsystems which can be customized based on magnetic resonance image measurements in women with and without prolapse. The customizable structural parameters include presence of levator ani (LA) avulsion, hiatus size, anterior vaginal wall dimension, attachment fascia length and apical location in addition to the tissue material properties and intra-abdominal pressure loading. After customization, the FE model was loaded with increasing intra-abdominal pressure (0–100 cmH 2 O) and solved using ABAQUS explicit solver. We were able to rapidly construct anatomically based FE models with specific structural geometry which reflects the morphology changes often observed in women with prolapse. At maximum loading, simulated structural deformations have similar anatomical characteristics to those observed during clinical exams and stress magnetic resonance images. Simulation results showed the presence of LA muscle avulsion negatively impacts the pelvic floor support. The normal model with intact muscle had the smallest exposed vaginal length of 11 mm, while the bilateral avulsion produced the largest exposed vaginal length at 24 mm. The unilateral avulsion model had an exposed vaginal length of 18 mm and also demonstrated a tipped perineal body similar to that seen in clinical observation. Increasing the hiatus size, vaginal wall length and fascia length also resulted in worse pelvic floor support, increasing the exposed vaginal length from 18 mm in the base model to 33 mm, 54 mm and 23.5 mm, respectively. The developed POP-SIM1.0 can simulate the anatomical structure changes often observed in women with prolapse. Preliminary results showed that the presence of LA avulsion, enlarged hiatus, longer vaginal wall and fascia length can result in larger prolapse at simulated maximum Valsalva.

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Electroretinographic Determination of Spectral Sensitivity in Albino and Pigmented Brook Trout (Salvelinus fontinalis, Mitchill)

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y71-146 ◽

1971 ◽

Vol 49 (12) ◽

pp. 1030-1037 ◽

Cited By ~ 7

Author(s):

H. Kobayashi ◽

M. A. Ali

Keyword(s):

Absorption Spectrum ◽

Spectral Sensitivity ◽

Brook Trout ◽

Salvelinus Fontinalis ◽

Narrow Band ◽

Visible Spectrum ◽

The Difference

A technique for recording electroretinograms from the unpunctured eyes in situ of living, anesthetized fish is described. This technique permits the use of the same fish in a number of experiments over a period of weeks, months, or years. Using this technique the spectral sensitivity of dark-adapted (scotopic) and light-adapted (photopic) fish was measured at 13 bands of the visible spectrum. The scotopic curves of albino and pigmented trout thus obtained in the winter have their maxima around 525 nm which differ from that of the absorption spectrum of the scotopic pigment in situ and in vitro of older fish obtained in the summer. The photopic curve of the pigmented fish is a broad one with humps around 425 nm, 545 nm, and 595 nm. The albino's curve has a relatively narrow band with a peak around 630 nm and a shoulder at about 550 nm. The difference between the shapes of the two curves may be ascribed to the increase in the intensity of light of longer wavelengths within the eyeball of the albino, due to reflection from blood vessels and sclera caused by the absence of pigmentation.

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Atomic absorption background of Ba in EXAFS analysis of BaFe12O19nanoparticles

Journal of Synchrotron Radiation ◽

10.1107/s0909049511010181 ◽

2011 ◽

Vol 18 (4) ◽

pp. 557-563 ◽

Cited By ~ 3

Author(s):

Jana Padežnik Gomilšek ◽

Alojz Kodre ◽

Iztok Arčon ◽

Simone de Panfilis ◽

Darko Makovec

Keyword(s):

Aqueous Solution ◽

Absorption Spectrum ◽

Atomic Absorption ◽

Energy Region ◽

Structural Parameters ◽

Simple Analytical Model ◽

Absorption Signal ◽

X Ray ◽

Exafs Analysis ◽

Atomic Absorption Spectra

The approximate barium X-ray atomic absorption in the energy region ofL-edges is reconstructed from the absorption spectrum of an aqueous solution of BaCl2. The result is corroborated by comparison with pure atomic absorption spectra of neighbour elements Xe and Cs. The application of the atomic absorption signal as a proper EXAFS background is demonstrated and discussed in the analysis of Ba hexaferrite nanoparticles with a very weak structural signal. The essential gain is found in the decrease of uncertainty intervals of structural parameters and their correlations. A simple analytical model of the absorption background for the practical EXAFS analysis is demonstrated.

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