High-contrast and reversible scattering switching via hybrid metal-dielectric metasurfaces

Novel types of optical hybrid metasurfaces consist of metallic and dielectric elements are designed and proposed for controlling the interference between magnetic and electric modes of the system, in a reversible manner. By employing the thermo-optical effect of silicon and gold nanoantennas we demonstrate an active control on the excitation and interference between electric and magnetic modes, and subsequently, the Kerker condition, as a directive radiation pattern with zero backscattering, via temperature control as a versatile tool. This control allows precise tuning optical properties of the system and stimulating switchable sharp spectral Fano-like resonance. Furthermore, it is shown that by adjusting the intermediate distance between metallic and dielectric elements, opposite scattering directionalities are achievable in an arbitrary wavelength. Interestingly, this effect is shown to have a direct influence on nonlinear properties, too, where 10-fold enhancement in the intensity of third harmonic light can be obtained for this system, via heating. This hybrid metasurface can find a wide range of applications in slow light, nonlinear optics and bio-chemical sensing.

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Features of the Christian values system

Ukrainian Religious Studies ◽

10.32420/2004.29.1481 ◽

2004 ◽

pp. 21-29

Author(s):

G.V. Pyrog

Keyword(s):

Public Opinion ◽

Religious Beliefs ◽

Religious Values ◽

Direct Influence ◽

Moral Norms ◽

Value System ◽

Christian Religion ◽

Mass Consciousness ◽

Wide Range ◽

Very High

In domestic scientific and public opinion, interest in religion as a new worldview paradigm is very high. Today's attention to the Christian religion in our society is connected, in our opinion, with the specificity of its value system, which distinguishes it from other forms of consciousness: the idea of God, the absolute, the eternity of moral norms. That is why its historical forms do not receive accurate characteristics and do not matter in the mass consciousness. Modern religious beliefs do not always arise as a result of the direct influence of church preaching. The emerging religious values are absorbed in a wide range of philosophical, artistic, ethical ideas, acting as a compensation for what is generally defined as spirituality. At the same time, the appeal to Christian values became very popular.

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Femtosecond Laser Fabrication of Hybrid Metal-Dielectric Structures with Nonlinear Photoluminescence

Photonics ◽

10.3390/photonics8040121 ◽

2021 ◽

Vol 8 (4) ◽

pp. 121

Author(s):

Ekaterina Ponkratova ◽

Eduard Ageev ◽

Filipp Komissarenko ◽

Sergei Koromyslov ◽

Dmitry Kudryashov ◽

...

Keyword(s):

Visible Spectral Region ◽

Single Step ◽

Hybrid Nanostructures ◽

Nonlinear Properties ◽

Nanophotonic Devices ◽

Sensing Applications ◽

Structure Morphology ◽

Wide Range ◽

Nonlinear Signal ◽

Dielectric Structures

Fabrication of hybrid micro- and nanostructures with a strong nonlinear response is challenging and represents a great interest due to a wide range of photonic applications. Usually, such structures are produced by quite complicated and time-consuming techniques. This work demonstrates laser-induced hybrid metal-dielectric structures with strong nonlinear properties obtained by a single-step fabrication process. We determine the influence of several incident femtosecond pulses on the Au/Si bi-layer film on produced structure morphology. The created hybrid systems represent isolated nanoparticles with a height of 250–500 nm exceeding the total thickness of the Au-Si bi-layer. It is shown that fabricated hybrid nanostructures demonstrate enhancement of the SHG signal (up to two orders of magnitude) compared to the initial planar sample and a broadband photoluminescence signal (more than 200 nm in width) in the visible spectral region. We establish the correlation between nonlinear signal and phase composition provided by Raman scattering measurements. Such laser-induced structures have significant potential in optical sensing applications and can be used as components for different nanophotonic devices.

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High Flux Reactor Review and Reactivity Control Analysis

10.1115/icone28-64723 ◽

2021 ◽

Author(s):

Wang Lin ◽

Xu Wei ◽

Xie Fei

Keyword(s):

Control Analysis ◽

Control Mechanisms ◽

General Description ◽

High Flux ◽

High Flux Reactor ◽

Wide Range ◽

Versatile Tool ◽

Flux Reactor ◽

Safety Operation ◽

Reactivity Insertion

Abstract For over 60 years, research reactors have provided the world with a versatile tool to test materials and promote irradiation research, as well as to produce radioisotopes for medical treatments. The High Flux Reactor (HFR), as a water moderated and cooled, beryllium-reflected reactor has awarded more attention in recent years. There is a wide range of designs and applications for HFRs that based on their own situation to meet research requirements. For the purpose of reducing the volume and mass of the reactor, as well as ensuring the safety operation, it is necessary to determine the most effective reactivity control scheme, and analyze the corresponding reactivity insertion accidents. This paper is going to investigate typical high flux reactors within the same type with HFETR, summarize general description and characteristics, the uses of the high flux reactor, and reactivity control mechanisms. In addition, the associated reactivity insertion accidents were presented and analyzed. The analysis result will provide some references to further design and construction of high flux reactor.

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Green light emission in silicon through slow light enhanced third-harmonic generation in photonic crystal waveguides

Conference on Lasers and Electro-Optics/International Quantum Electronics Conference ◽

10.1364/cleo.2009.jtuf5 ◽

2009 ◽

Author(s):

C. Monat ◽

B. Corcoran ◽

C. Grillet ◽

D. J. Moss ◽

B. J. Eggleton ◽

...

Keyword(s):

Photonic Crystal ◽

Harmonic Generation ◽

Slow Light ◽

Light Emission ◽

Green Light ◽

Third Harmonic Generation ◽

Photonic Crystal Waveguides ◽

Third Harmonic ◽

Green Light Emission

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High-Energy Small- and Wide-Angle X-Ray Scattering: A Versatile Tool for Materials Analysis

X-Rays in Mechanical Engineering Applications ◽

10.1115/imece2004-62458 ◽

2004 ◽

Author(s):

Jonathan Almer

Keyword(s):

High Energy ◽

Real Space ◽

Wide Angle ◽

X Ray ◽

Study Materials ◽

X Ray Scattering ◽

Angle Scattering ◽

Wide Range ◽

Versatile Tool ◽

Ray Scattering

Acquisition of microstructural information during realistic service conditions is an ongoing need for fundamental materials insight and computational input. In addition, for engineering applications it is often important to be able to study materials over a wide range of penetration depths, from the surface to bulk. In this presentation we discuss developments at the Sector 1-ID beamline of the Advanced Photon Source (APS) to utilize high-energy x-ray scattering for such studies. The use of high-energies (~80 keV) provides a highly penetrating probe, with sampling depths up to several mm in most materials. Through the development and use of high-energy optics, we can perform both small- and wide-angle scattering (SAXS/WAXS), to probe a large range of sample dimensions in reciprocal space (ranging from Angstroms to hundreds of nanometers), with real space resolutions ranging from microns to mm.

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