Broadband, wide-angle and tunable terahertz absorber based on cross-shaped graphene arrays

We theoretically and numerically demonstrate a tunable and wide-angle terahertz absorber, which is composed of multilayer graphene-dielectric grating and bottom metal substrate. Numerical simulation shows that the proposed absorber has the advantage of dynamically tunable range from 1.015 THz to 1.165 THz when the chemical potential of graphene increases from 10 meV to 150 meV. The absorption efficiency can reach a high value of 99%. To show the working mechanism of absorption, the near field distributions of magnetic components are presented at the absorption wavelength. We also demonstrate that the tunable range of absorption can be engineered by designing the geometry parameters. In addition, it is shown that the designed absorber can maintain the good performance of absorption over a wide incident angle from [Formula: see text] to [Formula: see text] under TM-polarization.

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Ultra-broadband wide-angle terahertz absorber realized by a doped silicon metamaterial

Optics Communications ◽

10.1016/j.optcom.2020.125835 ◽

2020 ◽

Vol 471 ◽

pp. 125835 ◽

Cited By ~ 7

Author(s):

Mingwei Jiang ◽

Zhengyong Song ◽

Qing Huo Liu

Keyword(s):

Wide Angle ◽

Terahertz Absorber ◽

Doped Silicon

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CBED Shadow Images and Cs:Aberration Measurement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055813 ◽

1982 ◽

Vol 40 ◽

pp. 696-697

Author(s):

R. W. Carpenter ◽

I.Y.T. Chan ◽

J. M. Cowley

Keyword(s):

Focal Point ◽

Spherical Aberration ◽

Optic Axis ◽

Wide Angle ◽

Caustic Surface ◽

Convergent Beam

Wide-angle convergent beam shadow images(CBSI) exhibit several characteristic distortions resulting from spherical aberration. The most prominent is a circle of infinite magnification resulting from rays having equal values of a forming a cross-over on the optic axis at some distance before reaching the paraxial focal point. This distortion is called the tangential circle of infinite magnification; it can be used to align and stigmate a STEM and to determine Cs for the probe forming lens. A second distortion, the radial circle of infinite magnification, results from a cross-over on the lens caustic surface of rays with differing values of ∝a, also before the paraxial focal point of the lens.

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Reconstruction of Chitin-Protein Complexes Using Correlation Averaging Methods: Ovipositor of the Ichneumon Fly Megarhyssa

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000143 ◽

1980 ◽

Vol 38 ◽

pp. 38-39

Author(s):

L. T. Germinario ◽

J. Blackwell ◽

J. Frank

Keyword(s):

Protein Complexes ◽

Hexagonal Lattice ◽

Uranyl Acetate ◽

Optical Diffraction ◽

Insect Cuticle ◽

High Dose ◽

Wide Angle ◽

X Ray ◽

Averaging Methods ◽

Digital Correlation

This report describes the use of digital correlation and averaging methods 1,2 for the reconstruction of high dose electron micrographs of the chitin-protein complex from Megarhyssa ovipositor. Electron microscopy of uranyl acetate stained insect cuticle has demonstrated a hexagonal array of unstained chitin monofibrils, 2.4−3.0 nm in diameter, in a stained protein matrix3,4. Optical diffraction Indicated a hexagonal lattice with a = 5.1-8.3 nm3 A particularly well ordered complex is found in the ovipositor of the ichneumon fly Megarhyssa: the small angle x-ray data gives a = 7.25 nm, and the wide angle pattern shows that the protein consists of subunits arranged in a 61 helix, with an axial repeat of 3.06 nm5.

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Developmental Risk Through a Wide-Angle Lens

Contemporary Psychology ◽

10.1037/026675 ◽

1987 ◽

Vol 32 (1) ◽

pp. 54-55

Author(s):

Jack P. Shonkoff

Keyword(s):

Wide Angle ◽

Developmental Risk ◽

Wide Angle Lens

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Wide angle view of the Universe

Nature India ◽

10.1038/nindia.2016.86 ◽

2016 ◽

Keyword(s):

Wide Angle ◽

The Universe

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Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonators

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200145 ◽

2020 ◽

Vol 91 (3) ◽

pp. 30901

Author(s):

Yibo Tang ◽

Longhui He ◽

Jianming Xu ◽

Hailang He ◽

Yuhan Li ◽

...

Keyword(s):

Transverse Electric ◽

Surface Current ◽

Dielectric Substrate ◽

Transverse Magnetic ◽

Metamaterial Absorber ◽

Absorption Peak ◽

Dual Band ◽

Single Peak ◽

Wide Angle ◽

Surface Current Density

A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.

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