Artículos de revistas: "Optical wave synthesis"

1

Mills, D. W. y L. S. Tamil. "Synthesis of guided wave optical interconnects". IEEE Journal of Quantum Electronics 29, n.º 11 (1993): 2825–34. http://dx.doi.org/10.1109/3.248942.

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2

Smokal, Vitaliy, Oksana Krupka, Aleksey Kolendo, Beata Derkowska, Robert Czaplicki y Bouchta Sahraoui. "Synthesis, polymerization ability, nonlinear optical properties of methacrylic monomers and polymers with benzylidene moiety". Chemistry & Chemical Technology 1, n.º 3 (15 de septiembre de 2007): 131–35. http://dx.doi.org/10.23939/chcht01.03.131.

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New methacrylic monomers, their polymers with benzylidene fragment were synthesized. Structures of all compounds were determined by HNMR, UV- spectroscopies. The third order nonlinear optical properties of oxazolone, thiazolidinone and thiohydantoin containing compounds were investigated in solutions using degenerate four wave mixing (DFWM) method at 532 nm.

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3

Khaefi, Sara, Alireza Mallahzadeh y Mohammad Hossein Amini. "Flat-topped pattern synthesis of optical leaky-wave antennas". Optics Communications 485 (abril de 2021): 126737. http://dx.doi.org/10.1016/j.optcom.2020.126737.

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4

Jiang, Zhi Hao, Jeremy P. Turpin, Kennith Morgan, Bingqian Lu y Douglas H. Werner. "Spatial transformation-enabled electromagnetic devices: from radio frequencies to optical wavelengths". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, n.º 2049 (28 de agosto de 2015): 20140363. http://dx.doi.org/10.1098/rsta.2014.0363.

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Transformation optics provides scientists and engineers with a new powerful design paradigm to manipulate the flow of electromagnetic waves in a user-defined manner and with unprecedented flexibility, by controlling the spatial distribution of the electromagnetic properties of a medium. Using this approach, over the past decade, various previously undiscovered physical wave phenomena have been revealed and novel electromagnetic devices have been demonstrated throughout the electromagnetic spectrum. In this paper, we present versatile theoretical and experimental investigations on designing transformation optics-enabled devices for shaping electromagnetic wave radiation and guidance, at both radio frequencies and optical wavelengths. Different from conventional coordinate transformations, more advanced and versatile coordinate transformations are exploited here to benefit diverse applications, thereby providing expanded design flexibility, enhanced device performance, as well as reduced implementation complexity. These design examples demonstrate the comprehensive capability of transformation optics in controlling electromagnetic waves, while the associated novel devices will open up new paths towards future integrated electromagnetic component synthesis and design, from microwave to optical spectral regimes.

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5

Krishnamurthi, Vijay, Brent Bailey y Frederick Lanni. "3-D optical transfer in excitation field synthesis microscopes". Proceedings, annual meeting, Electron Microscopy Society of America 53 (13 de agosto de 1995): 64–65. http://dx.doi.org/10.1017/s0424820100136696.

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Excitation field synthesis (EFS) refers to the use of an interference optical system in a direct-imaging microscope to improve 3D resolution by axially-selective excitation of fluorescence within a specimen. The excitation field can be thought of as a weighting factor for the point-spread function (PSF) of the microscope, so that the optical transfer function (OTF) gets expanded by convolution with the Fourier transform of the field intensity. The simplest EFS system is the standing-wave fluorescence microscope, in which an axially-periodic excitation field is set up through the specimen by interference of a pair of collimated, coherent, s-polarized beams that enter the specimen from opposite sides at matching angles. In this case, spatial information about the object is recovered in the central OTF passband, plus two symmetric, axially-shifted sidebands. Gaps between these bands represent "lost" information about the 3D structure of the object. Because the sideband shift is equal to the spatial frequency of the standing-wave (SW) field, more complete recovery of information is possible by superposition of fields having different periods. When all of the fields have an antinode at a common plane (set to be coincident with the in-focus plane), the "synthesized" field is peaked in a narrow infocus zone.

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6

Shaker, Reyhane, Alireza Mallahzadeh y Mohammad Hossein Amini. "Low side-lobe level pattern synthesis of optical leaky-wave antennas". Optik 242 (septiembre de 2021): 167192. http://dx.doi.org/10.1016/j.ijleo.2021.167192.

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7

SENTHILKUMARAN, PARAMASIVAM y FRANK WYROWSKI. "Phase synthesis in wave-optical engineering: mapping- and diffuser-type approaches". Journal of Modern Optics 49, n.º 11 (septiembre de 2002): 1831–50. http://dx.doi.org/10.1080/09500340210140533.

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8

Foord, A. P., P. A. Davies y P. A. Greenhalgh. "Synthesis of microwave and millimetre-wave filters using optical spectrum-slicing". Electronics Letters 32, n.º 4 (1996): 390. http://dx.doi.org/10.1049/el:19960243.

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9

Inaba, H., T. Ikegami, Feng-Lei Hong, A. Onae, Y. Koga, T. R. Schibli, K. Minoshima et al. "Phase locking of a continuous-wave optical parametric oscillator to an optical frequency comb for optical frequency synthesis". IEEE Journal of Quantum Electronics 40, n.º 7 (julio de 2004): 929–36. http://dx.doi.org/10.1109/jqe.2004.830211.

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10

Wang, Jing-Sheng. "Newly Installed Radio and Optical Telescopes in China". Publications of the Astronomical Society of Australia 9, n.º 1 (1991): 60–61. http://dx.doi.org/10.1017/s1323358000024899.

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AbstractNew radio and optical telescopes installed in recent years in China are summarised. These include the 2.16-m optical telescope, the solar magnetic field telescope, the Miyun synthesis radio telescope, the 1.26-m infrared telescope (Beijing Astronomical Observatory), the 25-m radio telescope as the first station of China’s VLBI network, the 1.56-m astrometric telescope (Shanghai Observatory), and the 13.7-m millimetre wave radio telescope.

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11

Chen-Bin Huang, D. E. Leaird y A. M. Weiner. "Synthesis of Millimeter-Wave Power Spectra Using Time-Multiplexed Optical Pulse Shaping". IEEE Photonics Technology Letters 21, n.º 18 (septiembre de 2009): 1287–89. http://dx.doi.org/10.1109/lpt.2009.2024957.

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12

Park, Hyeonsoo, Hansik Yun, Chulsoo Choi, Jongwoo Hong, Hwi Kim y Byoungho Lee. "Huygens’ optical vector wave field synthesis via in-plane electric dipole metasurface". Optics Express 26, n.º 8 (11 de abril de 2018): 10649. http://dx.doi.org/10.1364/oe.26.010649.

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13

Wani, Irshad A., Aparna Ganguly, Jahangeer Ahmed y Tokeer Ahmad. "Silver nanoparticles: Ultrasonic wave assisted synthesis, optical characterization and surface area studies". Materials Letters 65, n.º 3 (febrero de 2011): 520–22. http://dx.doi.org/10.1016/j.matlet.2010.11.003.

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14

NAJAM, Hanaa M. y Hanaa M. YASEEN. "SYNTHESIS OF SM3+ DOPED WITH TIO2 NANOPARTICLES POWDER AS MID-IR OPTICAL FILTER". MINAR International Journal of Applied Sciences and Technology 03, n.º 01 (1 de marzo de 2021): 1–7. http://dx.doi.org/10.47832/2717-8234.1-3.1.

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Samarium ions doped TiO2 nanoparticles were prepared successfully via Sol-Gel Technique with varying conditions. Effects of Sm3+ doping concentrations on the optical properties in the mid-infrared region was studied. FTIR spectra for pure and doped samples after annealing process show a single transition peak at wave number around 1109 cm-1 and 1116 cm-1 respectively, the wave number of the single transition peak depends on the Sm+3 doping ratio. By Comparing with wavelength of the high transition ratio of the pure TiO2 sample, slightly decries shift on the peak wavelength occur with an increment of doping concentration ratio. The FTIR spectrum gives a good indication the direction of synthesis of optical band-pass filter at a wavelength around 8.964µm (~1116 Cm-1).

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15

Jinzhong, Liu y Zhang Yu. "A binary population synthesis study on gravitational wave sources". Proceedings of the International Astronomical Union 11, A29B (agosto de 2015): 365–66. http://dx.doi.org/10.1017/s1743921316005548.

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AbstractGravitational waves (GW) are a natural consequence of Einstein's theory of gravity (general relativity), and minute distortions of space-time. Gravitational Wave Astronomy is an emerging branch of observational astronomy which aims to use GWs to collect observational data about objects such as neutron stars and black holes, about events such as supernovae and about the early universe shortly after the big bang.This field will evolve to become an established component of 21st century multi-messenger astronomy, and will stand shoulder-to-shoulder with gamma-ray, x-ray, optical, infrared and radio astronomers in exploring the cosmos. In this paper, we state a recent theoretical study on GW sources, and present the results of our studies on the field using a binary population synthesis (BPS) approach, which was designed to investigate the formation of many interesting binary-related objects, including close double white dwarfs, AM CVn stars, ultra-compact X-ray binaries(UCXBs), double neutron stars, double stellar black holes. Here we report how BPS can be used to determine the GW radiation from double compact objects.

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16

Zhou, Shutong, Xiaojuan Lv, Minghui Li, Zijian Gao, Shengnan Tu, Shanshan Qiao, Mengjia Mo, Xu Tang, Yemei Wang y Shasha Sun. "Synthesis, Optical Properties, and Fluorescence Cell Imaging of Novel Mixed Fluorinated Subphthalocyanines". Molecules 28, n.º 2 (11 de enero de 2023): 725. http://dx.doi.org/10.3390/molecules28020725.

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Subphthalocyanines (SubPcs) are a kind of tripyrrolic macrocycle with a boron atom at their core. Incorporating different units onto the SubPc periphery can endow them with various unique properties. Herein, a series of novel fluorinated low-symmetry SubPc derivatives containing chlorine groups (F8-Cl4-SubPc, F4-Cl8-SubPc) and methoxy groups (F8-(OCH3)2-SubPc) were synthesized and characterized by spectral methods (MS, FT-IR, 1H, 13C, 11B, and 19F NMR spectroscopy), and the effect of the peripheral substituents on their electronic structure of low-symmetry macrocycle was investigated by cyclic voltammetry, theoretical calculation, electronic absorption, and emission spectroscopy. In contrast to perfluorinated SubPcs, these low-symmetry SubPcs revealed non-degenerate LUMO and LUMO + 1 orbitals, especially F8-(OCH3)2-SubPc, which was consistent with the split Q-band absorptions. The cyclic voltammetry revealed that these SubPcs exhibited two or three reduction waves and one oxidation wave, which is consistent with the reported SubPcs. Finally, an intracellular fluorescence imaging study of these compounds revealed that these compounds could enter cancer cells and be entrapped in the lysosomes, which provides a possibility of future applications in lysosome fluorescence imaging and targeting.

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17

Chen, X. X., S. F. He, D. H. Xia, Z. J. Wang y Y. Pan. "Synthesis of two quasi-optical polarizers for the multi-frequency high-power millimeter wave system". Review of Scientific Instruments 93, n.º 10 (1 de octubre de 2022): 104707. http://dx.doi.org/10.1063/5.0110833.

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Millimeter wave systems based on powerful gyrotron can deliver megawatt microwave power, which is an important auxiliary heating method for magnetic confinement fusion devices. Reflective gratings are normally used as quasi-optical polarizers for polarization control of the wave in such systems. Based on the coordinate transformation method, we developed a numerical code to study the broadband polarization strategy. By considering the synthesis of two polarizers, we designed a pair of polarizers in the W band. Calculation results indicated that almost arbitrary polarization can be achieved in a wide frequency range. To verify the design, we set up a low-power test platform and experiments were carried out. The performance of the polarizers was tested from 80 to 105 GHz with a step of 5 GHz. The test results agreed well with the numerical results, indicating that the design is reasonable. With the development of multi-frequency gyrotrons, the study in this paper can be used as a reference for the design of broadband polarizers of multi-frequency millimeter wave systems.

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18

O'Brien, S., S. Osborne, D. Bitauld, N. Brandonisio, A. Amann, R. Phelan, B. Kelly y J. O'Gorman. "Optical Synthesis of Terahertz and Millimeter-Wave Frequencies With Discrete Mode Diode Lasers". IEEE Transactions on Microwave Theory and Techniques 58, n.º 11 (noviembre de 2010): 3083–87. http://dx.doi.org/10.1109/tmtt.2010.2074931.

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19

Frank, Curtis W. "Polymer Materials Science: Novel Synthesis and Characterization of Supermolecular Structures". MRS Bulletin 16, n.º 7 (julio de 1991): 20–22. http://dx.doi.org/10.1557/s0883769400056499.

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The two feature articles in this issue present numerous contrasts, but both reflect the vitality of research in polymer science today. David Tirrell and co-authors paint a picture of how the techniques of molecular biology may be applied to the synthesis of novel “proteinlike” polymers with control over molecular weight, composition, and stereoregularity that is unprecedented in the realm of traditional polymer chemistry. Wolfgang Knoll turns his attention to ultrathin polymer films with thicknesses comparable to molecular chain dimensions and demonstrates how evanescent wave optical methods may be used to provide spectroscopic as well as imaging information on the characterization of these “restricted geometry” systems.Both authors address the issue of supermolecular structure, whether approached from the synthetic or physical chemical viewpoints. Tirrell describes a series of target polymers, expressed by genetically engineered microorganisms, which may provide a fundamental understanding and control over chain folding, a critical morphological feature governing solid-state behavior of synthetic polymers. Knoll analyzes the fundamentals of evanescent wave optical methods for interrogating the molecular organization in polymer films that have considerable potential in electronic or photonic applications.

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20

Dolmatov, Alexey V., Mikhail V. Pinchuk y Alexey V. Sergeychev. "Optical measurement and analysis of microstructure of wave combustion in Ni-Al". Yugra State University Bulletin 11, n.º 2 (15 de junio de 2015): 14–26. http://dx.doi.org/10.17816/byusu201511214-26.

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In this paper study the microstructure of the wave self-propagating high-temperature synthesis (SHS) to find the relationship between the rate of the reaction front, the characteristic size of foci and the combustion temperature. Measure the dynamics of the temperature field SHS process was carried out using of the original optical complex of micropyrometer with a spatial resolution of 5.9 mkm and a speed of recording up to 10,000 frames per second. A method of analysis of thermal data implemented on the basis of ergodic model of the wave regime SHS and MATLAB. In the experiment is varied composition Ni-Al and its initial temperature. The experiment results approximated of the quadratic dependence of the rate of the front reaction on the hearth size, and inverse dependence of the hearth size on combustion temperature and initial temperature of the reaction mixture.

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21

Acedo, P., G. Carpintero, A. R. Criado, C. de Dios y K. Yvind. "Photonic synthesis of continuous-wave millimeter-wave signals using a passively mode-locked laser diode and selective optical filtering". Microwave and Optical Technology Letters 54, n.º 6 (20 de marzo de 2012): 1416–19. http://dx.doi.org/10.1002/mop.26822.

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22

Sarip, Nurulnadia, Che Ani Norhidayah, Sharul Ashikin Kamaruddin, Farhanahani Mahmud, Siti Nooraya Mohd Tawil y Mohd Zainizan Sahdan. "Synthesis and Characterization of Zinc Oxide Nanostructures by Different Sonication Period". Advanced Materials Research 925 (abril de 2014): 110–14. http://dx.doi.org/10.4028/www.scientific.net/amr.925.110.

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Zinc oxide (ZnO) is a wide band gap semiconductor material (3.37 eV) with numerous present applications such as varistors, surface acoustic wave devices and future biomedical applications. ZnO nanorods were grown under specific growth condition by an inexpensive and simple, chemical bath deposition method on ZnO seeded glass substrates. Study of the ZnO nanorods over different precursors, i.e zinc acetate dehydrate and zinc nitrate hexahydrate, and sonication period ranging from 0 to 120 seconds by field emission scanning electron microscope (FESEM), including the nanorod size and the surface morphology, will be demonstrated in this paper. Characterization of the ZnO film using both X-ray diffraction (XRD) and UV-Vis spectroscopy will be established in determining the optimal composition along with the optical properties, respectively.

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23

Piestun, Rafael, Boris Spektor y Joseph Shamir. "Wave fields in three dimensions: analysis and synthesis". Journal of the Optical Society of America A 13, n.º 9 (1 de septiembre de 1996): 1837. http://dx.doi.org/10.1364/josaa.13.001837.

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24

Bardasevska, S. D., I. M. Budzulyak, S. I. Budzulyak, B. I. Rachiy, R. V. Ilnytskyi, B. N. Kulchytskyi y Yu Yu Starchuk. "Method of obtaining and studying the optical properties of carbon quantum dots." Фізика і хімія твердого тіла 19, n.º 3 (3 de octubre de 2019): 226–29. http://dx.doi.org/10.15330/pcss.19.3.226-229.

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The proposed method of synthesis of CQDs on the basis of nanoporous carbon obtained from plant raw materials. It is established that in the short-wave region a band is registered, which is due to the exciton mechanism of recombination, whereas in the long-wavelength region it is related to the state of defects. The kinetics of PL extinction is not strictly exponential, which most likely indicates the distributed nature of fading from individual emitters.

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25

Furusato, Tomohiro, Mitsuru Sasaki, Yoshinobu Matsuda y Takahiko Yamashita. "Underwater shock wave induced by pulsed discharge on water". Journal of Physics D: Applied Physics 55, n.º 11 (13 de diciembre de 2021): 115203. http://dx.doi.org/10.1088/1361-6463/ac3f57.

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Abstract Plasmas on liquids have provided significant applications in material, environmental, and biological sciences. The mechanisms of these chemical reactions in liquids have been primarily described by the plasma–liquid interactions and convection by an electrohydrodynamic flow. Although shock waves play a significant role in radical formation, agitation and cell destruction, not much information is available on underwater shock waves induced by the surface discharge on water. In this study, an underwater shock wave generated by the pulsed surface discharge on water using the laser shadowgraph method has been demonstrated. The results reveal that the shock wave generated by the discharge on water was transmitted into the water. The mean velocity of the shock wave reached 1.7 km s−1. The results indicate that the surface discharge accelerates the reaction in the water by the combined action of the underwater shock wave and the plasma reaction at the air–water interface. The results are expected to aid in the understanding the mechanisms of existing applications, such as decomposition, synthesis, and sterilization.

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26

SRINIVASU, CH, M. A. SAMI, A. EDUKONDALU y SYED RAHMAN. "SYNTHESIS AND SPECTROSCOPY OF SOME QUATERNARY OXYFLUORIDE GLASSES DOPPED WITH COPPER". International Journal of Modern Physics: Conference Series 22 (enero de 2013): 284–91. http://dx.doi.org/10.1142/s2010194513010246.

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Electron paramagnetic resonance (EPR) and optical absorption spectra of copper ions in xLiF-(50-x)Li2O-20SrO-30Bi2O3 glass system have been studied. MDSC studies showed that the glass transition temperature decreases with LiF content. Optical absorption spectra of the pure glasses reveled that the cut off wave length increased and optical band gap energy decreased with increase in LiF content. EPR spectra of all the glass samples exhibit resonance signals characteristic of Cu2+ ions. The Cu2+ ions are in well-defined axial sites but subjected to small distortion leading to the broadening of the spectra. The spin-Hamiltonian parameter values indicate that the ground state of Cu2+ is d x2 y2 and the site symmetry around Cu2+ ions is tetragonally distorted octahedral. The optical absorption spectra exhibited a broad band corresponding to the d-d transition bands of Cu2+ ion. By correlating EPR and optical absorption data, the bond parameters are evaluated from various techniques.

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27

Apretna, T., N. Nilforoushan, J. Tignon, S. Dhillon, F. Carosella, R. Ferreira, E. Lhuillier y J. Mangeney. "Coherent THz wave emission from HgTe quantum dots". Applied Physics Letters 121, n.º 25 (19 de diciembre de 2022): 251101. http://dx.doi.org/10.1063/5.0134396.

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Mercury telluride (HgTe) nanocrystals (NCs) are very promising for THz technology as they exhibit broad THz absorption resonances and a carrier lifetime of a few picoseconds as well as being easily fabricated using solution synthesis. In this work, we show their light emission properties in the THz spectral range, up until now unexplored, and show how THz pulse generation can be used for microscopic insights into these NCs. In particular, we report on coherent THz emission from large HgTe NCs excited by linearly polarized optical pulses via second-order nonlinear effects. The peak emission frequency is tunable from 0.4 to 0.8 THz by varying incident angles of optical pulses from 0° to 45°. Our results reveal that the THz emission is induced by transient photocurrents arising from both photogalvanic and photon drag effects. By pushing the light emission of colloidal quantum dots down to the THz spectral range, our study expands the application fields of NCs, especially toward the development of easily integrable and tunable THz emitters and quantum THz devices.

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28

Fisun, Anatoly Ivanovich. "Constructive Synthesis of Dispersive Oscillation Systems of Quasi-Optical Solid-State Millimeter-Wave Sources". Telecommunications and Radio Engineering 54, n.º 2 (2000): 82–91. http://dx.doi.org/10.1615/telecomradeng.v54.i2.90.

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29

Xiao, S., L. Hollberg y S. A. Diddams. "Low-noise synthesis of microwave and millimetre-wave signals with optical frequency comb generator". Electronics Letters 45, n.º 3 (2009): 170. http://dx.doi.org/10.1049/el:20093593.

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30

Hyodo, M., K. S. Abedin y N. Onodera. "Generation of arbitrary optical waveforms by Fourier synthesis using three continuous-wave semiconductor lasers". Electronics Letters 36, n.º 3 (2000): 224. http://dx.doi.org/10.1049/el:20000212.

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31

Molnar, Eva, Emese Gál, Luiza Găină, Castelia Cristea y Luminița Silaghi-Dumitrescu. "Ethyne Functionalized Meso-Phenothiazinyl-Phenyl-Porphyrins: Synthesis and Optical Properties of Free Base Versus Protonated Species". Molecules 25, n.º 19 (4 de octubre de 2020): 4546. http://dx.doi.org/10.3390/molecules25194546.

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Synthesis, structural characterization and photophysical properties for a series of new trans-A2B2- and A3B-type ethynyl functionalized meso-phenothiazinyl-phenyl porphyrin derivatives are described. The new compounds displayed the characteristic porphyrin absorption spectra slightly modified by weak auxochromic effects of the substituents and fluorescence emission in the range of 651–659 nm with 11–25% quantum yields. The changes recorded in the UV-vis absorption spectra in the presence of trifluoroacetic acid (TFA) are consistent with the protonation of the two internal nitrogen atoms of the free-base porphyrin (19 nm bathochromic shift of the strong Soret band and one long wave absorption maxima situated in the range of 665–695 nm). Protonation of the phenothiazine substituents required increased amounts of TFA and produced a distinct hypsochromic shift of the long wave absorption maxima. The density functional theory (DFT) calculations of a porphyrin dication pointed out a saddle-distorted porphyrin ring as the ground-state geometry.

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32

Hassan, Qusay Mohammed Ali. "Two-photon absorption-based optical limiting in 2-(2-methoxybenzyllideneamino)-5-methylphenylmercuric chloride-doped PMMA film". Modern Physics Letters B 28, n.º 10 (20 de abril de 2014): 1450079. http://dx.doi.org/10.1142/s0217984914500791.

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The synthesis and the linear and optical limiting properties of a 2-(2-methoxybenzyllideneamino)-5-methylphenylmercuric chloride-doped poly(methylmethacrylate) (PMMA) film are described. The sample exhibits strong optical power limiting under continuous wave (cw) laser at the experimental wavelength. The mechanisms for the optical limiting were discussed on the basis of the two-photon absorption involved in the process. The nonlinear absorption coefficient β of the sample is estimated and its value is found to be 67 × 10-2 cm/W. Our study indicated that the investigated compound-doped PMMA film is a potential candidate for optical limiting applications in low power cw regime.

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33

Haigh, S. J., H. Sawada y Angus I. Kirkland. "Optimal tilt magnitude determination for aberration-corrected super resolution exit wave function reconstruction". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, n.º 1903 (28 de septiembre de 2009): 3755–71. http://dx.doi.org/10.1098/rsta.2009.0124.

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Transmission electron microscope (TEM) images recorded under tilted illumination conditions transfer higher spatial frequencies than axial images. This super resolution information transfer is highly directional in a single image, but can be extended in all directions through the use of complementary beam tilts during exit wave function reconstruction. We have determined the optimal experimental tilt magnitude for aperture synthesis in an aberration-corrected TEM. It is shown that electron-optical aberration correction allows the use of larger tilt angles and reduces the constraints that are imposed on experimental data acquisition in an uncorrected microscope. We demonstrate that, in many cases, the resolution improvement achievable is now limited by the sample and not by instrumental parameters. An exit wave function is presented that has been successfully reconstructed from a dataset of aberration-corrected images, including images acquired at a beam tilt of 18 mrad, which clearly demonstrates a resolution improvement from 0.11 nm to better than 0.08 nm at 200 kV.

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34

Heo, Jae-Hee, Jin-Young You y Young-Min Kang. "Synthesis, characterization, and electromagnetic wave absorption properties of Sr3Co2Fe24O41 hexaferrites". Journal of Magnetism and Magnetic Materials 550 (mayo de 2022): 169051. http://dx.doi.org/10.1016/j.jmmm.2022.169051.

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35

Manaa, Hacene, Devrim Attila, Ayse Gul Gurek, Sughra Mohamed, Fadheela A. Alawainati, Adnan Jaafar y Fryad Z. Henari. "Synthesis, Fluorescence and Nonlinear Optical Properties of Phthalocyanine Derivatives in the Continuous-wave and Pulsed Excitation Regimes-=SUP=-*-=/SUP=-". Оптика и спектроскопия 129, n.º 5 (2021): 626. http://dx.doi.org/10.21883/os.2021.05.50889.1054-20.

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In this work, the photo-physical properties of seven different phthalocyanine derivatives are studied, with a focus on their transparency spectral range. Two compounds among them are recently synthesised. The investigations include synthesis, photoluminescence, absorptive and refractive nonlinear properties, and optical limiting performances. The compounds are found to be emitting interesting broad fluorescence bands in the visible range. The nonlinear optical properties are investigated with the help of Z-scan technique, with both a continuous laser at 488, 514.5 and 632.8 nm, and with a pulsed laser at 532 nm. The sign and the magnitude of the nonlinear refractive index, third-order susceptibility, and nonlinear absorption coefficient have been evaluated in the seven compounds. The optical limiting performance of each compound was also evaluated in the continuous and pulsed laser excitation regimes. Keywords:

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36

Bahari, H. S., Z. Dehghani, E. Saievar-Iranizad, M. Molaei y M. H. Majles Ara. "Synthesis and Investigation of the Linear and Nonlinear Optical Properties of Alloyed CdSe0.3Te0.7Nanocrystals". International Journal of Nanoscience 13, n.º 01 (febrero de 2014): 1450007. http://dx.doi.org/10.1142/s0219581x14500070.

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Alloyed CdSe 0.3 Te 0.7nanocrystals (NCs) were prepared by a thermochemical method using Thioglycolic acid (TGA) as a capping agent molecule. X-ray diffraction (XRD) and Transmission electron microscopy (TEM) analysis demonstrated hexagonal phase NCs with an average size of around 2.5 nm. Synthesized NCs indicated a narrow band emission with a peak located at 561 nm. Nonlinear optical (NLO) properties of the CdSe 0.3 Te 0.7NCs have been investigated by z-scan technique using Continuum Wave H e– Ne laser. The nonlinear absorption coefficient and nonlinear refraction index were obtained in the order of 10-2 and 10-8, respectively. The results revealed that these NCs exhibit strong NLO properties effects such as self-defocusing and two photons absorption.

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37

Albadri, Raed Ashraf Kamil y Khalid Saeed Lateef Al-Badri. "Simulation Study of Perfect Dual Band Microwave Metasurface Absorber". NeuroQuantology 20, n.º 3 (26 de marzo de 2022): 160–65. http://dx.doi.org/10.14704/nq.2022.20.3.nq22055.

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This study presents analytical results using the CST software for a very simple design of an electromagnetic wave absorber with a negative refractive index, a copper circular-shape printed on an insulating layer separating it from a flat ground layer of copper. This design provides two absorption bands with an absorption capacity of 97.55%. This absorption is due to the dipole oscillation. Also, controlling the shape dimensions and thickness of the insulating layer leads to good results in the synthesis of the resonant frequency that contributes to the applications of energy collection and protection from the effects of electromagnetic waves. The results gave the highest value of absorption with dielectric thickness h = 0.5 mm) and by selecting a proper the gap value for g = 0.3 mm. It is also worth noting that the design can be developed to operate in a wide range of frequencies such as microwaves, terahertz, up to optical frequencies, which may contribute to potential applications in many engineering and optical technologies.

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38

Valyanskii, S. I., E. K. Naimi y L. V. Kozhitov. "Functional 2D nanomaterials for optoelectronic equipment on the basis of langmuir–blodgett bacteriorhodopsin films". Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering 19, n.º 2 (30 de junio de 2016): 124–32. http://dx.doi.org/10.17073/1609-3577-2016-2-124-132.

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We have tested the possibility of using monomolecular layers of bacteriorhodopsin (BR) for the synthesis of highly sensitive and highly selective sensors based on second harmonic generation and surface plasma waves. We have used various methods to study the optical and nonlinear optical properties of Langmuir-Blodgett films of BR in order to clarify the extent to which specific properties of BR molecules are retained during their transfer from the surface of water to a solid substrate. We show that the second harmonic generation method is efficient for analyzing the molecular orientation and quality of Langmuir-Blodgett films. The experimental nonlinear optical susceptibility of second order BR molecules is 3.4 · 10-11m/V. The relative change in the resonant wave vector is (3.6 ± 0.1)·10-2at an excitation light wavelength of 630 nm. We have obtained a BR spectrum with the effective excitation by incident radiation of surface plasma waves. On the basis of these studies, we have proposed new schemes of biosensors operating on the basis of second harmonic generation and surface plasma resonance caused by fundamental frequency reflection from BR monomolecular layers. This scheme was tested for a model device and demonstrated the possibility of obtaining sensitivities of the order of 1011molecules/cm3.

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39

Wei, Hui Min, Nan Zhao, Nan Jiang, Wen Feng Duan y Bao Xiang Gao. "The Synthesis and Electro-Optical Properties of Perylene Dicarboximide Dimer with Electron Withdrawing Groups". Advanced Materials Research 936 (junio de 2014): 950–54. http://dx.doi.org/10.4028/www.scientific.net/amr.936.950.

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Perylene dicarboximide dimer with electron withdrawing groups were synthesized and fully characterized by 1H-NMR and 13C-NMR spectra. The effects of the substituted groups on the optical and electrochemical properties of the two compounds were investigated. The ∏-∏* absorption peak of the perylene dicarboximide dimer compounds were red shifted from 525nm to 535nm. The band gaps of the dimer could be tuned from 2.28 eV to 2.13 eV. The first reduction wave of the dimer with electron withdrawing groups is shifted by 60 mV to more positive potential compared to that of perylene dicarboximide, suggesting the enhanced electron affinity. Furthemore, the dimer exhibited intermolecular aggregation, and decrease fluorescence quantum yield.

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40

Gautam, Chandkiram, Anod Kumar Singh y Abhishek Madheshiya. "Preparation and Optical Investigations of [(Sr1-xBix)TiO3]-[2SiO2B2O3]-[CeO2] Glasses". Advances in Optics 2014 (30 de septiembre de 2014): 1–7. http://dx.doi.org/10.1155/2014/687207.

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We are reporting synthesis and structural and optical investigation of strontium bismuth titanate borosilicate glasses with addition of one mole percent cerium oxide (CeO2). Glasses were synthesized by conventional rapid melt quench method. XRD studies of the glass samples confirm the amorphous nature. Infrared absorption spectra various strontium bismuth titanate borosilicate glass samples having glass system 60[(Sr1-xBix)TiO3]-39[2SiO2B2O3]-1[CeO2] (x=0.0,0.1,0.2,0.4) were recorded over a continuous spectral range from 400 to 4000 cm−1. IR spectra were analyzed to determine and differentiate of various vibrational modes in the structural change. Raman spectroscopy of all glass samples was also carried out in the wave number range from 200 to 2000 cm−1.

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41

Bhaskar, M. Uday, S. Senthilkumar y G. Shankar. "Synthesis and Characterization of SEM, UV absorption coefficient and shock wave properties of Thiourea Sodium Sulphate crystal". Material Science Research India 17, n.º 3 (10 de diciembre de 2020): 270–75. http://dx.doi.org/10.13005/msri/170309.

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Single crystal of Thiourea Sodium Sulphate (TSS) was prepared by a slow evaporation technique. The optical absorption and absorption coefficient are studied by UV. Vis.-NIR The voids or defects of the TSS crystal were carried out by its surface morphology analysis by SEM. The NLO properties of shocked TSS single crystal were estimated by UV-Vis-NIR spectroscopic analysis. Finally the nonlinear optical property of TSS crystal was estimated by Second Harmonic Generation (SHG) and the suitability of present titled mono crystal against mechanical resistivity after the shock for non linear optics and for photonic application has been confirmed.

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42

Pribytkov, G. A., V. V. Korzhova, I. A. Firsina, A. V. Baranovskii y E. N. Korosteleva. "Study of gasless combustion products of Ti – Si – Al powder mixtures". Physics and Chemistry of Materials Treatment 1 (2022): 57–65. http://dx.doi.org/10.30791/0015-3214-2022-1-57-65.

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The combustion synthesis products in titanium, silicon and aluminum powder mixtures under the wave mode combustion are investigated by X-ray diffraction analysis and optical metallography. The synthesis products contain titanium silicide Ti5Si3 and titanium aluminide TiAl3, the ratio of which depends on the content of aluminum powder in the reaction mixtures. The combustion temperature of the mixtures decreases with an increase in the aluminum content. This is a consequence of the substitution of titanium aluminide in the synthesis products for titanium silicide, which has a multiple negative formation enthalpy compared to that of the silicide. Using ideas about the features of the growth of silicide and aluminide nuclei in a liquid metal solution, the effect of the combustion temperature on the dispersion of the structure of the synthesis products is discussed.

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43

Kotlikov, E. N., V. M. Andreev, Yu A. Novikova y G. V. Tereshchenko. "Synthesis of Polarizing Beamsplitters for the Far Infrared Spectral Range". LETI Transactions on Electrical Engineering & Computer Science 17, n.º 3 (2024): 5–11. http://dx.doi.org/10.32603/2071-8985-2024-17-3-5-11.

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The technique and results of the synthesis of polarization beam splitters for the long-wavelength infrared region of the spectrum of 8–14 microns are presented. In this range, bodies with temperatures around zero degrees Celsius begin to emit. In addition, this radiation has a low attenuation in a relatively humid or aerosol-saturated atmosphere. Therefore, it is widely used in night vision devices, rangefinders and thermal imaging cameras, including mobile systems with a variable angle of the optical axis relative to the angle of arrival of the incident electromagnetic wave. In systems with active illumination, polarized radiation and beam splitters are used to reduce the effect of backscattering interference. A review of patents and literature showed the absence of finished products for the considered wavelength range. In this paper, original designs of polarization beam splitters are proposed and their spectral optical characteristics are obtained.

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44

Bala Murali Krishna, M., L. Giribabu y D. Narayana Rao. "Ultrafast third order nonlinear optical properties of water soluble zinc-octacarboxy-phthalocyanine". Journal of Porphyrins and Phthalocyanines 16, n.º 09 (septiembre de 2012): 1015–23. http://dx.doi.org/10.1142/s108842461250040x.

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Synthesis and measurements of third order nonlinear optical (NLO) coefficients of water soluble zinc octacarboxy phthalocyanine (ZnOCPc) are reported here using different laser pulse durations. Nonlinear absorption and refraction behaviour in the nanosecond (ns), picosecond (ps) and femtosecond (fs) time domains were studied in detail. Three-photon absorption was the prevalent mechanism with femtosecond laser excitation whereas strong reverse saturable absorption due to dominant two-photon absorption (TPA) was observed with picosecond and nanosecond excitations. We have evaluated the sign and magnitude of the third order nonlinearity in fs, ps, and ns regimes. We observed large off-resonant second order hyperpolarizability (γ) with ultrafast nonlinear optical response in the femtosecond domain using degenerate four wave mixing (DFWM) technique. We also report the optical limiting characteristics and figure of merit (FOM) of ZnOCPc for optical switching.

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45

Zavyalova, Marina, Petr Zavyalov y Mark Savchenko. "FEATURES OF DESIGNING OPTICAL PRECISION POSITION SENSORS FOR OPERATIONAL CONTROL OF LASER SYNTHESIS OF MICRO AND NANOSTRUCTURES". Interexpo GEO-Siberia 8 (2019): 139–48. http://dx.doi.org/10.33764/2618-981x-2019-8-139-148.

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The design features of precision contactless position sensors for the operational control of high-speed laser synthesis of micro- and nanostructures is described. As a result of software simulation of the autofocus sensor based on the asymmetry of the wave front of the probing radiation, the influence of the Foucault knife position on the working range, which can be increased 10 times, has been established. The calculation and optimization of the fiber confocal sensor based on the chromatic coding method showed that the error in determining the surface position can be reduced several times by introducing a special apodizing mask into its scheme.

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46

Islam, Md Toriqul y Mool C. Gupta. "Synthesis, structural, optical, and electrical properties of continuous wave and pulse laser sintered semiconductor Ge films". Semiconductor Science and Technology 37, n.º 3 (31 de enero de 2022): 035015. http://dx.doi.org/10.1088/1361-6641/ac4d16.

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Abstract The crystallization process of Ge films by a continuous wave (CW) and a pulsed laser is very effective for producing smooth, homogeneous, and crack-free polycrystalline films to use in transistors, photodetectors, and photovoltaic applications. However, little progress has been made to directly crystallize Ge films based on micro/nanoparticles (NPs) using the laser sintering (LS) process. In this paper, a simultaneous LS and crystallization process of Ge micro/NPs to develop thick polycrystalline films on silicon substrates is demonstrated. Silicon substrates with a SiO2 insulating layer on top were considered for compatibility with complementary metal–oxide–semiconductor (CMOS) technology. The LS process was applied to solution deposited micro/NPs, 5 µm thick Ge films using both CW mode (infrared laser of wavelength 1070 nm) and pulse mode (UV laser of wavelength 355 nm) laser. After the LS process, around 2–2.5 µm thick film of polycrystalline Ge (pc-Ge) was achieved with optical and electrical properties comparable to traditionally developed chemical vapor deposited films. The crystallinity of the pc-Ge films was evaluated by Raman spectroscopy and x-ray diffraction (XRD). The laser-sintered films exhibited a Raman peak at 300 cm−1 and XRD 2θ peak at 27.35, which indicated the poly-crystalline structure. The fabricated film showed high hole mobility of 203 cm2 V−1 s−1, without any doping and film electrical resistivity value of 6.24 × 105 Ω-cm. The developed LS process allows the quick deposition of polycrystalline thick films, removing surface porosity and voids, increasing films adhesion with the substrate, and faster thermal annealing.

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47

Grèzes-Besset, C., F. Chazallet, G. Albrand y E. Pelletier. "Synthesis and research of the optimum conditions for the optical monitoring of non-quarter-wave multilayers". Applied Optics 32, n.º 28 (1 de octubre de 1993): 5612. http://dx.doi.org/10.1364/ao.32.005612.

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48

Hyodo, M., N. Onodera y K. Sarwar Abedin. "Fourier synthesis of 257 GHz optical pulse train by phaselocking of three continuous-wave semiconductor lasers". Electronics Letters 35, n.º 7 (1999): 564. http://dx.doi.org/10.1049/el:19990360.

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49

Fantoni, R., E. Borsella, S. Piccirillo, R. Ceccato y S. Enzo. "Laser synthesis and crystallographic characterization of ultrafine SiC powders". Journal of Materials Research 5, n.º 1 (enero de 1990): 143–50. http://dx.doi.org/10.1557/jmr.1990.0143.

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High purity, ultrafine SiC powders have been produced from gas phase reactants (SiH4, C2H2) in a CO2 laser induced process. The flow reactor designed to operate with a medium power (10–50 W) continuous wave CO2 laser source is described. The mechanism of gas phase reactions involved has been investigated by means of on-line optical diagnostics. Powders produced have been characterized by means of conventional chemical and spectroscopic methods. The x-ray results point out a growth mechanism by coalescence; i.e., whole islands move in the flame to take part in binary collisions, analogously to that observed for particles produced by inert gas evaporation.

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50

Jung, Sun-Shin, Young-Do Joo, S. Ghosh, B. N. Basu y Gun-Sik Park. "Synthesis of dielectric helix supports for wideband traveling-wave tubes". Microwave and Optical Technology Letters 32, n.º 3 (27 de diciembre de 2001): 231–35. http://dx.doi.org/10.1002/mop.10140.

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