Erbium energy bridging upconversion mechanism studies on BAKL: Er3+/Yb3+ glass-ceramics and simultaneous enhancement of color purity of the green luminescence

Dalton Transactions ◽

10.1039/d1dt03918k ◽

2022 ◽

Author(s):

Prasenjit Prasad Sukul ◽

Kaushal Kumar ◽

Hendrik Christoffel Swart

Keyword(s):

Glass Ceramics ◽

Ultra Violet ◽

Optically Active ◽

Color Purity ◽

Green Luminescence ◽

Host Matrix ◽

Oxyfluoride Glasses ◽

Infra Red ◽

Upconversion Mechanism

Borate oxyfluoride glasses are transparent in the infra-red, ultra violet and visible regions and represent an ideal host matrix for optically active dopants. Due to their lower phonon energies compared...

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Optical properties of a thin layer of the Vanadium dioxide at the metal state

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v9i1.1479 ◽

2015 ◽

Vol 9 (1) ◽

pp. 2303-2310

Author(s):

Abderrahim Benchaib ◽

Abdesselam Mdaa ◽

Izeddine Zorkani ◽

Anouar Jorio

Keyword(s):

Optical Properties ◽

Thin Layer ◽

Vanadium Dioxide ◽

Ultra Violet ◽

Index Of Refraction ◽

Cost Of Energy ◽

Infra Red ◽

Metal State ◽

The Cost ◽

Reversible Phase

The vanadium dioxide VOâ‚‚ currently became very motivating for the nanotechnologiesâ€™ researchers. It makes party of the intelligent materials because these optical properties abruptly change semiconductor state with metal at a critical Â temperature Î¸ = 68Â°C. This transition from reversible phase is carried out from a monoclinical structure characterizing its semiconductor state at low temperature towards the metal state of this material which becomes tÃ©tragonal rutile for Â Î¸ Ëƒ 68Â°CÂ ; it is done during a few nanoseconds. Several studies were made on this material in a massive state and a thin layer. We will simulate by Maple the constant optics of a thin layer of VOâ‚‚ thickness z = 82 nm for the metal state according to the energy Ï‰ of the incidental photons in the energy interval: 0.001242 â‰¤ Ï‰(ev) â‰¤ 6, from the infra-red (I.R) to the ultra-violet (U.V) so as to be able to control the various technological nano applications, like the detectors I.R or the U.V,Â the intelligent windows toÂ increase Â the energy efficiency in the buildings in order to save the cost of energy consumption by electric air-conditioning and the paintings containing nano crystals of this material. The constant optics, which we will simulate, is: the index of refraction, the reflectivity, the transmittivity, the coefficient of extinction, the dielectric functions Ô‘â‚Â real part and Â Ô‘â‚‚Â imaginary part of the permittivity complexes Ô‘ of this material and the coefficient absorption.Â

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Optical properties of the Vanadium dioxide

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i2.1520 ◽

2015 ◽

Vol 8 (2) ◽

pp. 2148-2155 ◽

Cited By ~ 1

Author(s):

Abderrahim Benchaib ◽

Abdesselam Mdaa ◽

Izeddine Zorkani ◽

Anouar Jorio

Keyword(s):

Energy Efficiency ◽

Optical Properties ◽

Critical Temperature ◽

Thin Layer ◽

Dielectric Function ◽

Vanadium Dioxide ◽

Ultra Violet ◽

Index Of Refraction ◽

Practical Utility ◽

Infra Red

The vanadium dioxide is a material thermo chromium which sees its optical properties changing at the time of theÂ transition from the phase of semiconductor state â†” metal, at a critical temperature of 68Â°C. The study of the opticalÂ properties of a thin layer of VOâ‚‚ thickness 82 nm, such as the dielectric function, the index of refraction, the coefficient ofextinction, the absorptionâ€™s coefficient, the reflectivity, the transmittivity, in the photonic spectrum of energy Ï‰ located inthe interval: 0.001242 â‰¤ Ï‰ (ev) â‰¤ 6, enables us to control well its practical utility in various applications, like the intelligentpanes, the photovoltaic, paintings for increasing energy efficiency in buildings, detectors of infra-red (I.R) or ultra-violet(U.V). We will make simulations with Maple and compare our results with those of the literature

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New Polyporphyrin Arrays with Controlled Fluorescence Obtained by Diaxial Sn(IV)-Porphyrin Phenolates Chelation with Cu2+ Cation

Polymers ◽

10.3390/polym13050829 ◽

2021 ◽

Vol 13 (5) ◽

pp. 829

Author(s):

Galina M. Mamardashvili ◽

Dmitriy A. Lazovskiy ◽

Ilya A. Khodov ◽

Artem E. Efimov ◽

Nugzar Z. Mamardashvili

Keyword(s):

Chemical Species ◽

Ultra Violet ◽

X Rays ◽

Structure And Properties ◽

Paramagnetic Resonance ◽

1H Nuclear Magnetic Resonance ◽

Infra Red ◽

Connection Type ◽

Chelation Reaction ◽

Electron Paramagnetic

New coordination oligomers and polymers of Sn(IV)-tetra(4-sulfonatophenyl)porphyrin have been constructed by the chelation reaction of its diaxialphenolates with Cu2+. The structure and properties of the synthesized polyporphyrin arrays were investigated by 1H Nuclear Magnetic Resonance (1H NMR), Infra Red (IR), Ultra Violet - Visible (UV-Vis) and fluorescence spectroscopy, mass spectrometry, Powder X-Rays Diffraction (PXRD), Electron Paramagnetic Resonance (EPR), thermal gravimetric, elemental analysis, and quantum chemical calculations. The results show that the diaxial coordination of bidentate organic ligands (L-tyrazine and diaminohydroquinone) leads to the quenching of the tetrapyrrole chromophore fluorescence, while the chelation of the porphyrinate diaxial complexes with Cu2+ is accompanied by an increase in the fluorescence in the organo-inorganic hybrid polymers formed. The obtained results are of particular interest to those involved in creating new ‘chemo-responsive’ (i.e., selectively interacting with other chemical species as receptors, sensors, or photocatalysts) materials, the optoelectronic properties of which can be controlled by varying the number and connection type of monomeric fragments in the polyporphyrin arrays.

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Er-doped and Er, Yb co-doped oxyfluoride glasses and glass–ceramics, structural and optical properties

Optical Materials ◽

10.1016/j.optmat.2011.04.027 ◽

2011 ◽

Vol 33 (11) ◽

pp. 1630-1637 ◽

Cited By ~ 27

Author(s):

Radosław Lisiecki ◽

Elżbieta Augustyn ◽

Witold Ryba-Romanowski ◽

Michał Żelechower

Keyword(s):

Optical Properties ◽

Glass Ceramics ◽

Structural And Optical Properties ◽

Oxyfluoride Glasses ◽

Er Doped ◽

Co Doped

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Hydrogen Conversion in Nanocages

Hydrogen ◽

10.3390/hydrogen2020010 ◽

2021 ◽

Vol 2 (2) ◽

pp. 160-206

Author(s):

Ernest Ilisca

Keyword(s):

Ultra Violet ◽

Dipolar Interactions ◽

Nuclear Spins ◽

Reaction Heat ◽

Thermal Methods ◽

The Past ◽

Hydrogen Molecules ◽

Conversion Rates ◽

Catalytic Sites ◽

Infra Red

Hydrogen molecules exist in the form of two distinct isomers that can be interconverted by physical catalysis. These ortho and para forms have different thermodynamical properties. Over the last century, the catalysts developed to convert hydrogen from one form to another, in laboratories and industries, were magnetic and the interpretations relied on magnetic dipolar interactions. The variety concentration of a sample and the conversion rates induced by a catalytic action were mostly measured by thermal methods related to the diffusion of the o-p reaction heat. At the turning of the new century, the nature of the studied catalysts and the type of measures and motivations completely changed. Catalysts investigated now are non-magnetic and new spectroscopic measurements have been developed. After a fast survey of the past studies, the review details the spectroscopic methods, emphasizing their originalities, performances and refinements: how Infra-Red measurements characterize the catalytic sites and follow the conversion in real-time, Ultra-Violet irradiations explore the electronic nature of the reaction and hyper-frequencies driving the nuclear spins. The new catalysts, metallic or insulating, are detailed to display the operating electronic structure. New electromagnetic mechanisms, involving energy and momenta transfers, are discovered providing a classification frame for the newly observed reactions.

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Local Structure and Er3+ Emission from Pseudo-Amorphous GaN:Er Thin Films

MRS Proceedings ◽

10.1557/proc-536-81 ◽

1998 ◽

Vol 536 ◽

Author(s):

S. B. Aldabergenova ◽

M. Albrecht ◽

A. A. Andreev ◽

C. Inglefield ◽

J. Viner ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Amorphous Matrix ◽

Broad Band ◽

Resonant Absorption ◽

Absorption Bands ◽

Host Matrix ◽

Transmission Electron ◽

Infra Red ◽

Band Edge Luminescence

AbstractWe report on strong Er3+ luminescence in the visible and infra-red regions at room temperature in amorphous GaN:Er thin films prepared by DC magnetron co-sputtering. The intensity of the Er3+ luminescence at 1.535 μm corresponding to 4I13/2 → 4I15/2 transitions is greatly enhanced after annealing at 750°C. In this material GaN crystallites have formed and embedded in the continuous amorphous matrix. The crystallites are 4 to 7 nm in diameter as analyzed by high resolution transmission electron microscopy. The absorption edge, extending three orders of magnitude in absorption coefficient in the spectral range from 0.5 to 3.5 eV, is superimposed on resonant absorption bands of Er3+ ions.The total photoluminescence spectrum consists of welldefined Er3+ luminescence peaks imposed on a broad band edge luminescence from the amorphous GaN host matrix.

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II. The wave-lengths of A, a , and of prominent lines in the infra-red of the solar spectrum

Proceedings of the Royal Society of London ◽

10.1098/rspl.1883.0086 ◽

1883 ◽

Vol 36 (228-231) ◽

pp. 137-138

Keyword(s):

Solar Spectrum ◽

Ultra Violet ◽

Infra Red

M. Fievez has recently sent me a map of the solar spectrum from C to A* inclusive, and as part of this region is one which I have been measuring, I have examined the new publication with great interest. Photography and eye measurements do not exactly coincide in the detail of the grouping of the little a group as far as A, and A itself is shown by M. Fievez’s map as wanting some details which appear in the photographs. Thus in the photographs there are some seventeen lines, whilst in M. Fievez’s map there are but thirteen. Between A and a there are several lines of marked intensity in the photograph which are not shown in the new map. The wave-lengths of the different lines from above “ a ” to A are not the same as those given by Fievez, when they are taken from comparison photo-graphs of the 1st order of the red and 2nd of the ultra-violet on the same plate, or when checked by photographs of the 2nd order of the red with the 3rd order of the green taken in a similar manner. In my paper, “Phil. Trans.,” Part II, 1880, I gave a method of using mirrors by which this could be effected, but since Professor Rowland introduced his concave gratings this is much more readily carried out. He has kindly furnished me with gratings for the purpose, having about 14,400 lines to the inch, with focal distances of 7 feet 6 inches and 12 feet 6 inches respectively. These have been employed in determining the wave-lengths of this part of the spectrum. Cornu’s map was used as a reference for the ultra-violet wave-lengths, and Ångström’s map for those in the blue and green. The two maps may be taken as equally exact. The determination of A has been made by Maseart, Smyth, and others, besides Ångström and Langley, with discordant results. I think the above may be taken as accurate as are Cornu’s and Ångström maps.

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From Nanocomposite Aerogels to Glass Ceramics for Nuclear Wastes Containment

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.172-174.791 ◽

2011 ◽

Vol 172-174 ◽

pp. 791-796 ◽

Cited By ~ 3

Author(s):

Thierry Woignier ◽

Jerome Reynes ◽

Sylvie Calas

Keyword(s):

Viscous Flow ◽

Thermal Shock ◽

Nuclear Waste ◽

High Resistance ◽

Solid Phase ◽

Glass Ceramics ◽

Chemical Species ◽

Host Matrix ◽

Waste Containment ◽

Two Phases

Nanocomposite aerogel is proposed as a host matrix for the synthesis of glass ceramics. The large porosity is used as a sponge to incorporate chemical species getting a two phases material. We describe the steps of the synthesis of glass ceramics for nuclear waste containment, from nanocomposite aerogels loaded with actinides surrogates (Ce and Nd). The glass synthesis is obtained without melting, by a control of several solid phase transformations: sintering, viscous flow, crystallization and foaming. Thanks to their high resistance to thermal shock and water corrosion, these glass ceramics are certainly good candidates as actinides containment materials.

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