Generation of over 1000 Diffraction Spots from 2D Graded Photonic Super-Crystals

Safaa Hassan; Yan Jiang; Khadijah Alnasser; Noah Hurley; Hualiang Zhang; Usha Philipose; Yuankun Lin

doi:10.3390/photonics7020027

Generation of over 1000 Diffraction Spots from 2D Graded Photonic Super-Crystals

Photonics ◽

10.3390/photonics7020027 ◽

2020 ◽

Vol 7 (2) ◽

pp. 27

Author(s):

Safaa Hassan ◽

Yan Jiang ◽

Khadijah Alnasser ◽

Noah Hurley ◽

Hualiang Zhang ◽

...

Keyword(s):

Diffraction Pattern ◽

Cell Size ◽

Lattice Constant ◽

Field Intensity ◽

Lattice Model ◽

Dual Lattice ◽

First Order ◽

Super Cell ◽

First Time ◽

Fractional Orders

For the first time, we are able to generate over 1000 diffraction spots from a graded photonic super-crystal with a unit super-cell size of 12a × 12a where a is the lattice constant and hole radii are gradually changed in dual directions. The diffraction pattern from the graded photonic super-crystal reveals unique diffraction properties. The first order diffractions of (±1,0) or (0,±1) disappear. Fractional diffraction orders are observed in the diffraction pattern inside a square with vertices of (1,1), (1,−1), (−1,−1) and (−1,−1). The fractional diffraction can be understood from lattices with a period of a. However, a dual-lattice model is considered in order to explain higher-order diffractions. E-field intensity simulations show a coupling and re-distribution among fractional orders of Bloch waves. There are a total of 12 × 12 spots in E-field intensity in the unit supercell corresponding to 12 × 12 fractional diffraction orders in the diffraction pattern and 12 × 12 fractional orders of momentum in the first Brillouin zone in k-space.

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Высокоэффективная схема перераспределения оптического излучения на пространственных решетках атомных населенностей

Журнал технической физики ◽

10.21883/os.2019.07.47942.358-18 ◽

2019 ◽

Vol 127 (7) ◽

pp. 150

Author(s):

М.Ю. Гордеев ◽

Ю.В. Рождественский

Keyword(s):

Wave Field ◽

Diffraction Pattern ◽

Field Intensity ◽

Radiation Intensity ◽

Probe Wave ◽

Probe Field ◽

First Order ◽

Spatially Periodic ◽

Atomic States ◽

Intensity Transfer

AbstractThe radiation intensity redistribution of the probe field upon its scattering by spatially periodic atomic population gratings in a medium with a four-level tripod configuration of atomic states is investigated theoretically. Conditions are found under which a significant redistribution of the probe-wave field intensity occurs, and a “diffraction” pattern is formed with an efficient probe-field intensity transfer to the first-order maxima.

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ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b43168bfc21 ◽

2017 ◽

Author(s):

Svetlana Rubtsova ◽

Natalya Lyamina ◽

Aleksey Lyamin ◽

...

Keyword(s):

Black Sea ◽

Field Intensity ◽

Deep Water ◽

Coastal Waters ◽

Integrated Management ◽

Abiotic Factors ◽

Environmental Safety ◽

The Black Sea ◽

Intensity Increase ◽

First Time

The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.

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Non-Linear First-Order Differential Boundary Problems with Multipoint and Integral Conditions

Fractal and Fractional ◽

10.3390/fractalfract5010015 ◽

2021 ◽

Vol 5 (1) ◽

pp. 15

Author(s):

Misir J. Mardanov ◽

Yagub A. Sharifov ◽

Yusif S. Gasimov ◽

Carlo Cattani

Keyword(s):

Integral Equation ◽

Integral Boundary Conditions ◽

Contraction Mapping Principle ◽

Boundary Problems ◽

Integral Boundary ◽

Multipoint Problem ◽

First Order ◽

Banach Contraction ◽

First Time ◽

Banach Contraction Mapping Principle

This paper considers boundary value problem (BVP) for nonlinear first-order differential problems with multipoint and integral boundary conditions. A suitable Green function was constructed for the first time in order to reduce this problem into a corresponding integral equation. So that by using the Banach contraction mapping principle (BCMP) and Schaefer’s fixed point theorem (SFPT) on the integral equation, we can show that the solution of the multipoint problem exists and it is unique.

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The kinetics of the decarboxylation of β-resorcylic acid in catechol

Australian Journal of Chemistry ◽

10.1071/ch9760443 ◽

1976 ◽

Vol 29 (2) ◽

pp. 443 ◽

Cited By ~ 6

Author(s):

MA Haleem ◽

MA Hakeem

Keyword(s):

Rate Equation ◽

Kinetic Data ◽

Reaction Rate ◽

Complex Mechanism ◽

First Order ◽

Absolute Reaction Rate ◽

First Time ◽

Kinetics Of ◽

Absolute Reaction ◽

Reaction Rate Equation

Kinetic data are reported for the decarboxylation of β-resorcylic acid in resorcinol and catechol for the first time. The reaction is first order. The observation supports the view that the decomposition proceeds through an intermediate complex mechanism. The parameters of the absolute reaction rate equation are calculated.

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Quantum Gravity at the Corner

Universe ◽

10.3390/universe4100107 ◽

2018 ◽

Vol 4 (10) ◽

pp. 107 ◽

Cited By ~ 10

Author(s):

Laurent Freidel ◽

Alejandro Perez

Keyword(s):

Quantum Gravity ◽

Symplectic Form ◽

Direct Application ◽

Quantum Geometry ◽

Quantum Level ◽

Gravitational System ◽

Gauge Transformations ◽

First Order ◽

Conformal Field ◽

First Time

We investigate the quantum geometry of a 2d surface S bounding the Cauchy slices of a 4d gravitational system. We investigate in detail for the first time the boundary symplectic current that naturally arises in the first-order formulation of general relativity in terms of the Ashtekar–Barbero connection. This current is proportional to the simplest quadratic form constructed out of the pull back to S of the triad field. We show that the would-be-gauge degrees of freedo arising from S U ( 2 ) gauge transformations plus diffeomorphisms tangent to the boundary are entirely described by the boundary 2-dimensional symplectic form, and give rise to a representation at each point of S of S L ( 2 , R ) × S U ( 2 ) . Independently of the connection with gravity, this system is very simple and rich at the quantum level, with possible connections with conformal field theory in 2d. A direct application of the quantum theory is modelling of the black horizons in quantum gravity.

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Measurements of hydrogen cyanide (HCN) and acetylene (C<sub>2</sub>H<sub>2</sub>) from the Infrared Atmospheric Sounding Interferometer (IASI)

Atmospheric Measurement Techniques ◽

10.5194/amt-6-917-2013 ◽

2013 ◽

Vol 6 (4) ◽

pp. 917-925 ◽

Cited By ~ 9

Author(s):

V. Duflot ◽

D. Hurtmans ◽

L. Clarisse ◽

Y. R'honi ◽

C. Vigouroux ◽

...

Keyword(s):

Fourier Transform ◽

Hydrogen Cyanide ◽

Atmospheric Transport ◽

Trace Gases ◽

First Order ◽

Line Mixing ◽

Atmospheric Sounding ◽

First Time ◽

Order Comparison ◽

Emission Ratios

Abstract. Hydrogen cyanide (HCN) and acetylene (C2H2) are ubiquitous atmospheric trace gases with medium lifetime, which are frequently used as indicators of combustion sources and as tracers for atmospheric transport and chemistry. Because of their weak infrared absorption, overlapped by the CO2 Q branch near 720 cm−1, nadir sounders have up to now failed to measure these gases routinely. Taking into account CO2 line mixing, we provide for the first time extensive measurements of HCN and C2H2 total columns at Reunion Island (21° S, 55° E) and Jungfraujoch (46° N, 8° E) in 2009–2010 using observations from the Infrared Atmospheric Sounding Interferometer (IASI). A first order comparison with local ground-based Fourier transform infraRed (FTIR) measurements has been carried out allowing tests of seasonal consistency which is reasonably captured, except for HCN at Jungfraujoch. The IASI data shows a greater tendency to high C2H2 values. We also examine a nonspecific biomass burning plume over austral Africa and show that the emission ratios with respect to CO agree with previously reported values.

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Remarks Using the SEM method Species Seeds of Gentiana occurring in Turkey

Planta Daninha ◽

10.1590/s0100-83582017350100007 ◽

2017 ◽

Vol 35 (0) ◽

Author(s):

E. ALÇITEPE ◽

S. ERKEN ◽

F. GÜLBAG ◽

M.E. ÖZZAMBAK

Keyword(s):

Cell Size ◽

Morphological Character ◽

Seed Shape ◽

Different Types ◽

Seed Micromorphology ◽

Periclinal Walls ◽

First Time ◽

Seed Characteristics ◽

Wing Cell

ABSTRACT Seeds of eleven perennial Gentiana collected from Turkey were analyzed using the SEM method. Other species excluding G. septemfida, G. boissieri, G. gelida were studied for the first time. They were identified and compared in terms of seed characteristics and surface ornamentations. Major characteristics including the outer periclinal walls of testa, sculpting of inner periclinal walls, seed shape, seed and testa cell, wing cell size, thickness of testa wall and seed shape have been proposed for Turkey Gentiana. They are divided into different types, such as no wing, chalazal wing, incomplete discoid wing, complete discoid wing according to the outer periclinal walls of testa. Considering primary sculpting of seeds, irregularly striate and shallowly reticulate type is observed. Anticlinal walls of G. olivieri, G. boissieri and G. gelida are curved, while others are straight. G. lutea has the largest mean seed (4.20 x 4.40 mm), while G. cruciata (0.67 x 0.60 mm) and G. olivieri have the smallest mean seeds (0.67 x 0.67 mm). Seed micromorphology can be used together with morphological character to form classifications in studied specimens for Gentiana genus.

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Sodium carbonate revisited

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768103009017 ◽

2003 ◽

Vol 59 (3) ◽

pp. 337-352 ◽

Cited By ~ 46

Author(s):

Michal Dusek ◽

Gervais Chapuis ◽

Mathias Meyer ◽

Vaclav Petricek

Keyword(s):

Sodium Carbonate ◽

Harmonic Approximation ◽

Temperature Phase ◽

X Ray Diffraction ◽

Anhydrous Sodium Carbonate ◽

First Order ◽

Commensurate Phase ◽

Na Ions ◽

Fifth Order ◽

First Time

We present the structure of anhydrous sodium carbonate at room temperature (phase γ) and 110 K (phase δ) based on single-crystal X-ray diffraction data. The incommensurate phase γ was determined almost 30 years ago in the harmonic approximation using one modulation wave and first-order satellites. In our work we use satellites up to fifth order and additional harmonic waves to model the anharmonic features of the structure. The commensurate phase δ is presented for the first time. Using the superspace approach, both phases are compared in order to find common trends in the whole range of the sodium carbonate phases. We present arguments supporting the hypothesis that the driving force of the phase transitions may originate in the unsaturated bonding potential of one of the Na ions.

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Integrability via Functional Expansion for the KMN Model

Symmetry ◽

10.3390/sym12111819 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1819

Author(s):

Radu Constantinescu ◽

Aurelia Florian

Keyword(s):

Differential Equations ◽

Traveling Wave ◽

Nonlinear Differential Equations ◽

Traveling Wave Solutions ◽

Auxiliary Equation ◽

First Order ◽

Second Order Differential Equations ◽

Functional Expansion ◽

Wave Solutions ◽

First Time

This paper considers issues such as integrability and how to get specific classes of solutions for nonlinear differential equations. The nonlinear Kundu–Mukherjee–Naskar (KMN) equation is chosen as a model, and its traveling wave solutions are investigated by using a direct solving method. It is a quite recent proposed approach called the functional expansion and it is based on the use of auxiliary equations. The main objectives are to provide arguments that the functional expansion offers more general solutions, and to point out how these solutions depend on the choice of the auxiliary equation. To see that, two different equations are considered, one first order and one second order differential equations. A large variety of KMN solutions are generated, part of them listed for the first time. Comments and remarks on the dependence of these solutions on the solving method and on form of the auxiliary equation, are included.

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