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IEEE Symposium on Nuclear Science (NSS/MIC)

作者： P. A. P. Calò S. Petrignani C. Marzocca B. Markovic A. Dragone Department of Electric and Information Engineering DEI Politecnico di Bari Bari Italy SLAC TID-AIR research group SLAC National Accelerator Laboratory Menlo Park CA USA

ISBN: (数字)9781728141640

ISBN: (纸本)9781728141657

The present work describes a new channel architecture suited to reading out Silicon Photomultipliers (SiPM). The aim is to develop a multichannel Application-Specific Integrated Circuit (ASIC) in a standard CMOS 130 nm technology that achieves excellent timing accuracy while fully exploiting the dynamic range of large area SiPMs. The sensor is AC-coupled to the differential front-end, which features two separated timing and charge signal processing paths. The first one exploits a differential input current-mode preamplifier and an embedded Time-to-Digital Converter (TDC) that exhibits a 10 ps binning. Accurate timing and low jitter are also attained by means of a high-speed discriminator with threshold adjustable in small steps just above the baseline, which operates on the very steep edge of the output signal produced by the preamplifier. The charge measurement signal path is based on an active-RC integrator, a peak detector and an Analog-to-Digital Converter (ADC). Operating the front-end at 1.2 v supply voltage, with a power consumption of 10 mW, a simulated Single-photon Time Resolution (SPTR) of 78 ps at Full-Width Half Maximum (FWHM) is achieved, linearly covering an input dynamic range of 1280 pC that corresponds to ~8000 photoelectrons with a SiPM gain of ~10 6 .

关键词： Detectors Preamplifiers Charge measurement photonics Timing Resistance Dynamic range

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Selective laser melting of borosilicate glass using ultrashort laser pulses 5

Selective laser melting of borosilicate glass using ultrasho...

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5th Meeting of Laser 3D Manufacturing at photonics West conference

作者： Seyfarth, B. Schade, L. Ullsperger, T. Matthaeus, G. Tuennermann, A. Nolte, S. Friedrich Schiller Univ Jena IAP Albert Einstein Str 15 D-07745 Jena Germany Fraunhofer Inst Appl Opt & Precis Engn IOF High Performance Ctr Photon Albert Einstein Str 7 D-07745 Jena Germany Fraunhofer Inst Appl Opt & Precis Engn IOF Albert Einstein Str 7 D-07745 Jena Germany

ISBN: (数字)9781510615328

ISBN: (纸本)9781510615328

Within the field of laser assisted additive manufacturing, the application of ultrashort pulse lasers for selective laser melting came into focus recently. In contrast to conventional lasers, these systems provide extremely high peak power at ultrashort interaction times and offer both the opportunity of nonlinear absorption and the potential to control the thermal impact at the vicinity of the processed region by tailoring the pulse repetition rate. Consequently, transparent materials like borosilicate glass or opaque materials with extremely high melting points like copper, tungsten or even special composites like AlSi40 can be processed. In this publication, we present the selective laser melting of glass by using 500 fs laser pulses at MHz repetition rates emitted at a center wavelength of 515 nm. In order to identify an appropriate processing window, a detailed parameter study was performed. We demonstrate the fabrication of porous bulk glass parts as well as the realization of structures featuring thicknesses below 30 mu m, which is below typical achieved structural sizes using pulsed or CO2 laser [1]. In contrast to alternative approaches [2], due to the nonlinear absorption and therefore complete melting of the material, there was no need for binding materials. This work demonstrates the potential for 3D printing of glass using the powder bed approach.

关键词： laser processing additive manufacturing glass ultrashort laser pulses selective laser melting

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Study of the processes of three-dimensional printing of caprolactone copolymers with methylphosphate groups

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IOP conference Series: Materials Science and Engineering 2020年第1期848卷

作者： A O Mariyanats A v Mironov I E Nifant'ev A v Shlyakhtin v K Popov Institute of Photon Technologies of Federal Scientific Research Centre 'Crystallography and Photonics' Russian Academy of Sciences Troitsk Moscow 108840 Russia. Lomonosov Moscow State University Department of Chemistry Moscow 119991 Russia.

Reconstruction of the damaged or missed organs or skeleton fragments is an ambitious target for regenerative medicine. Tissue engineering construction (TEC) comprising three-dimensional bioresorbable scaffold and living cells can become native tissue substitute. Scaffold should correspond to strict requirements. Generally, its physical-mechanical and biochemical characteristics should be comparable with tissue to be replaced. Besides, resorption rate of scaffold material should correlate with the tissue regeneration rate in each case. Thus, the effect of scaffold manufacturing methods on its properties is an important point in TEC design and fabrication. At present study, thermo-extrusion 3D printing of bioresorbable scaffolds based on polycaprolactone and its copolymer with polyethylene glycol and methylphosphate groups, synthesized by novel chemical route, was investigated. Scaffold surface morphology and its internal structures were studied by optical and scanning electron microscopy. The effect of thermal-induced degradation on polymers properties at various 3D printing processing parameters was analysed by gel-permeation chromatography, differential scanning calorimetry and mechanical testing. It was shown that optimizing experimental parameters the developed methods of thermo-extrusion 3D printing enable effective polymer scaffolds fabrication in accordance with their 3D computer model without significant changes of physicochemical properties of initial materials.

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Plasmonic Modulators for Microwave photonics Applications

Plasmonic Modulators for Microwave Photonics Applications

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Asia Communications and photonics conference (ACP)

作者： Burla, Maurizio Bonjour, Romain Salamin, Yannick Abrecht, Felix C. Haffner, Christian Heni, Wolfgang Hoessbacher, Claudia Baeuerle, Benedikt Josten, Arne Fedoryshyn, Yuriy Johnston, Peter v. Elder, Delwin L. Dalton, Larry R. Leuthold, Juerg Swiss Fed Inst Technol Inst Electromagnet Fields Gloriastr 35 CH-8092 Zurich Switzerland Univ Washington Dept Chem Seattle WA 98195 USA

We discuss the potential of ultrafast (>170 GHz) and ultra-compact (10s mu m(2)) plasmonic modulators on silicon for microwave photonics applications, with emphasis on mm wave and sub-THz wireless communications an... 详细信息

ISBN: (纸本)9781943580347

关键词： Plasmons Modulation Microwave communication Microwave photonics Nonlinear optics Microwave filters

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Enabling photonic Integration Technology for Microwave photonics in 5G Systems 19

Enabling Photonic Integration Technology for Microwave Photo...

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19th International conference on Transparent Optical Networks (ICTON)

作者： Tsokos, C. Groumas, P. Katopodis, v. Avramopoulos, H. Kouloumentas, Ch. Natl Tech Univ Athens Athens 15573 Greece Optagon Photon Eleftheriou Venizelou 47 Athens 15351 Greece

ISBN: (纸本)9781538608593

Within the European project HAMLET, we develop a large scale photonic integrated circuit as a flexible interface between the optical front-haul part and the wireless access part at the remote antenna units (RAU) of future 5G networks. The circuit will be based on the hybrid integration of a polymer platform (PolyBoard) with a low-loss silicon-nitride platform (TriPleX), and will accommodate a number of processing functionalities in the digital and analog domains including optical beamforming. The analog optical link on-chip will be based on the use of graphene-based electro-absorption modulators in the polymer part of the circuit and will be able to transfer through the optical beamforming network radio signals at 28 GHz with 1 Gbaud symbol rate and modulation format up to 64-QAM. In this paper, we present early experimental results with bulk components that emulate the operation and evaluate the expected performance of our optical system on-chip.

关键词： microwave photonics 5G systems optical beam forming network analog photonic link electroabsorption modulator Mach-Zehnder modulator

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Advances in infrared GRIN: a review of novel materials towards components and devices 3

Advances in infrared GRIN: a review of novel materials towar...

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conference on Advanced Optics for Defense Applications - Uv through LWIR III

作者： Richardson, Kathleen Kang, Myungkoo Sisken, Laura Yadav, Anupama Blanco, Cesar Antia, Michael Novak, Spencer Smith, Charmayne Buff, Andy Lepicard, Antoine Dussauze, Marc Schwarz, Casey M. Kuebler, Stephen M. Grabill, Chris Pantano, Carlo G. Mayer, Theresa S. Pogrebnyakov, Alexej v. Rivero-Baleine, Clara Kirk, Andrew Mensah, Samantha Driggers, Megan Hu, Juejun Lin, Pao-Tai Agarwal, Anuradha M. Li, Cheng Deng, Weiwei Univ Cent Florida Coll Opt & Photon 4304 Scorpius St Orlando FL 32816 USA Univ Cent Florida Dept Mat Sci & Engn 4304 Scorpius St Orlando FL 32816 USA Univ Cent Florida Chem 4304 Scorpius St Orlando FL 32816 USA Univ Bordeaux CNRS UMR 5255 ISM 351 Cours Liberat F-33405 Talence France Ursinus Coll Dept Phys 601 E Main St Collegeville PA 19426 USA Penn State Univ Dept Mat Sci & Engn University Pk PA 16802 USA Penn State Univ Dept Elect Engn University Pk PA 16802 USA Clemson Univ Dept Mat Sci & Engn Clemson SC 29634 USA Lockheed Martin Corp 5600 Sandlake Rd Orlando FL 32819 USA MIT Dept Mat Sci & Engn Mat Res Lab 77 Massachusetts Ave Cambridge MA 02139 USA Lightpath Technol Orlando FL 32816 USA Virginia Polytech Univ Blacksburg VA 24061 USA Texas A&M Univ College Stn TX 77843 USA Southern Univ Sci & Technol Shenzhen 518055 Peoples R China PNNL Richland WA 99354 USA IRFlex Danville VA 24540 USA

ISBN: (数字)9781510617667

ISBN: (纸本)9781510617667

Novel optical materials capable of advanced functionality in the infrared will enable optical designs that can offer light-weight or small footprint solutions in both planar and bulk optical systems. UCF's Glass processing and Characterization Laboratory (GPCL) with our collaborators have been evaluating compositional design and processing protocols for both bulk and film strategies employing multi-component chalcogenide glasses (ChGs). These materials can be processed with broad compositional flexibility that allows tailoring of their transmission window, physical and optical properties, which allows them to be engineered for compatibility with other homogeneous amorphous or crystalline optical components. This paper reviews progress in forming ChG-based GRIN materials from diverse processing methodologies, including solution-derived ChG layers, poled ChGs with gradient compositional and surface reactivity behavior, na nocomposite bulk ChGs and glass ceramics, and meta-lens structures realized through multiphoton lithography (MPL).

关键词： chalcogenide glass GRIN multiphoton lithography poled chalcogenide glass optical nanocomposites glass ceramics integrated photonics

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Evaluation of the un-eliminated laser phase noise induced by interferometer imbalance in self-homodyne coherent optical RF receivers

Evaluation of the un-eliminated laser phase noise induced by...

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International conference on Optoelectronics and microelectronics Technology and Application (OMTA)

作者： Zhang, Huixing Wen, Aijun Gao, Yongsheng Zhang, Song Xiang, Shuiying Lin, Lin Xidian Univ State Key Lab Integrated Serv Networks Xian 710071 Peoples R China Chinese Acad Sci Xian Inst Opt & Precis Mech State Key Lab Transient Opt & Photon Xian 710119 Peoples R China

ISBN: (数字)9781510609907

ISBN: (纸本)9781510609891;9781510609907

Coherent optical RF receivers constructed in self-homodyne configurations have gained considerable attention due to its simplicity and cost-efficiency. Rigorous symmetry is required in such system to suppress the laser phase noise. A method for evaluation of the un-eliminated laser phase noise in self-homodyne coherent optical RF receivers has been presented in this paper. In our proposed scheme, the un-eliminated laser phase noise is acquired by simply inserting an FBG in the in-phase arm and is found to be dependent on the interferometer asymmetry, i.e., the path imbalance of the interferometer arms. With series of simulations, the variance of the un-eliminated laser phase noise obtained by our method becomes larger when the path imbalance is increasing. The simulation results show that, variance increases with the asymmetrical time delays of two interferometer arms. Therefore, this method is very helpful in obtaining further insight into the system symmetry and is also a good guidance for the adjustment of the interferometer architecture to achieve the optimized path equality.

关键词： Radio-over-fiber (ROF) Digital signal processing Laser phase noise Self-homodyne coherent detection

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Monitoring of laser material processing using machine integrated low-coherence interferometry 5

Monitoring of laser material processing using machine integr...

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5th International conference on Optical and photonics Engineering

作者： Kunze, Rouwen Koenig, Niels Schmitt, Robert Fraunhofer Inst Prod Technol IPT Steinbachstr 17 Aachen Germany Rhein Westfal TH Aachen Lab Machine Tools & Prod Engn WZL Aachen Germany

ISBN: (数字)9781510613737

ISBN: (纸本)9781510613737;9781510613720

Laser material processing has become an indispensable tool in modern production. With the availability of high power pico- and femtosecond laser sources, laser material processing is advancing into applications, which demand for highest accuracies such as laser micro milling or laser drilling. In order to enable narrow tolerance windows, a closed-loop monitoring of the geometrical properties of the processed work piece is essential for achieving a robust manufacturing process. Low coherence interferometry (LCI) is a high-precision measuring principle well-known from surface metrology. In recent years, we demonstrated successful integrations of LCI into several different laser material processing methods. Within this paper, we give an overview about the different machine integration strategies, that always aim at a complete and ideally telecentric integration of the measurement device into the existing beam path of the processing laser. Thus, highly accurate depth measurements within machine coordinates and a subsequent process control and quality assurance are possible. First products using this principle have already found its way to the market, which underlines the potential of this technology for the monitoring of laser material processing.

关键词： Laser material processing High-precision measuring Inline metrology Coaxial process monitoring Process feedback control

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Modeling and possible implementation of self-learning equivalence-convolutional neural structures for auto-encoding-decoding and clusterization of images 3

Modeling and possible implementation of self-learning equiva...

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3rd International conference on Applications of Optics and photonics

作者： Krasilenko, vladimir G. Lazarev, Alexander A. Nikitovich, Diana v. Vinnitsa Social Econ Inst 86-131 Kelestskaya Str UA-21021 Vinnitsa Ukraine Vinnytsia Natl Tech Univ Vinnytsia Ukraine

ISBN: (数字)9781510613843

ISBN: (纸本)9781510613843;9781510613836

Self-learning equivalent-convolutional neural structures (SLECNS) for auto-coding-decoding and image clustering are discussed. The SLECNS architectures and their spatially invariant equivalent models (SI EMs) using the corresponding matrix-matrix procedures with basic operations of continuous logic and non-linear processing are proposed. These SI EMs have several advantages, such as the ability to recognize image fragments with better efficiency and strong cross-correlation. The proposed clustering method of fragments with regard to their structural features is suitable not only for binary, but also color images and combines self-learning and the formation of weight clustered matrix-patterns. Its model is constructed and designed on the basis of recursively processing algorithms and to k-average method. The experimental results confirmed that larger images and 2D binary fragments with a large numbers of elements may be clustered. For the first time the possibility of generalization of these models for space invariant case is shown. The experiment for an image with dimension of 256x256 (a reference array) and fragments with dimensions of 7x7 and 21x21 for clustering is carried out. The experiments, using the software environment Mathcad, showed that the proposed method is universal, has a significant convergence, the small number of iterations is easily, displayed on the matrix structure, and confirmed its prospects. Thus, to understand the mechanisms of self-learning equivalence-convolutional clustering, accompanying her to the competitive processes in neurons, and the neural auto-encoding-decoding and recognition principles with the use of self-learning cluster patterns is very important which used the algorithm and the principles of non-linear processing of two-dimensional spatial functions of images comparison. These SIEMs can simply describe the signals processing during the all training and recognition stages and they are suitable for unipolar-coding multilevel

关键词： Self-learning equivalence-convolutional clustering neural structures two-dimensional spatial function autoencoding-decoding nonlinear processing image recognition

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Modeling the electron-photon interaction in monolayers of graphene and transition metal dichalcogenides in a tight binding approximation

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Journal of Physics: conference Series 2019年第2期1368卷

作者： S M R H Hussein S I Kharitonov N L Kazanskiy v S Pavelyev I N Kozlova Image Processing Systems Institute of RAS - Branch of the FSRC 'Crystallography and Photonics' RAS Molodogvardejskaya street 151 Samara Russia 443001 University of Karbala Karbala 56001 Iraq Samara National Research University Moskovskoe Shosse 34A Samara Russia 443086

In the presence of a strong electromagnetic field, the spectrum of charge carriers in a Dirac material is changed. The interaction of a linearly polarized field with electrons in the Dirac material leads to anisotropy. The anisotropy axis coincides with the direction of the electric field in the linearly polarized wave. We show that the major contribution to the interaction of electrons with an electromagnetic field comes from elastic scattering processes, whereas taking into account inelastic processes leads to an error of about 2%.

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