Articoli di riviste: "High pulsed power systems"

1

Chvykov, Vladimir. "High-Power Lasers". Encyclopedia 4, n. 3 (9 agosto 2024): 1236–49. http://dx.doi.org/10.3390/encyclopedia4030080.

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High-power lasers play an important role in modern science, industry, and medicine. A significant milestone was reached on 5 December 2022, when Inertial Confinement Nuclear Fusion (ICF) achieved scientific breakeven, releasing more energy than the input laser energy. Additionally, Extreme Ultraviolet Lithography (EUVL) has enabled the development of microchips with 3 nm process nodes, marking a leap in semiconductor technology. These examples, together with the recent achievement of 10 PW (1015 W) laser output, herald remarkable advancements in technology and science. Laser systems are broadly classified based on their operating regimes into two main categories: Continuous Wave (CW) operation, where the laser is continuously pumped and emits a steady beam of light, and the pulsed regime, in which the laser produces single or multiple pulses at various repetition rates. This review will primarily focus on pulsed laser systems, exploring their various types and recent technological advancements.

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Hongchao Hui, Hongchao Hui, Junyong Zhang Junyong Zhang, Xinghua Lu Xinghua Lu, Jiachen Zhang Jiachen Zhang, Xin Chen Xin Chen, Xiuqing Jiang Xiuqing Jiang, Baoqiang Zhu Baoqiang Zhu e and Zunqi Lin and Zunqi Lin. "Simulation study of broadband long-pulsed amplification in high-power laser systems". Chinese Optics Letters 14, n. 3 (2016): 031405–31408. http://dx.doi.org/10.3788/col201614.031405.

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Dong, Weigang, Lei Chen, Jian Qiu, Haozheng Shi, Hui Zhao e Kefu Liu. "The Cascade of High-Voltage Pulsed Current Sources". Electronics 13, n. 5 (28 febbraio 2024): 924. http://dx.doi.org/10.3390/electronics13050924.

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Currently, pulsed adders are used as pulsed voltage sources maturely. However, their use as pulsed current sources is significantly limited due to circuit impedance and the characteristics of power devices. This paper presents a simple yet effective design for a pulsed current source, incorporating a solid-state Marx pulsed adder as the primary power source and an inductor for energy storage. In the pulsed current source, a Marx pulsed adder produces high voltage to charge the inductor. Then, the stored inductance energy is converted to generate current pulses on the load; the amplitude of the pulsed current is unaffected by the load impedance within a certain range. The pulsed current source can be designed as a standard module, and several modules can form a cascade system for producing current pulses with higher voltage. Finally, a pulsed current source was developed, which can produce adjustable current pulses with high voltage. The design principles, control methods and the effects of the distribution parameters are described. The feasibility of the cascade pulsed power system was validated in experiments. Nine modules were connected to generate pulses of current 10 A on a 15 kΩ resistor.

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Chen, Fu-Zen, Yu-Cheng Song e Fu-Shun Ho. "An Efficiency Improvement Driver for Master Oscillator Power Amplifier Pulsed Laser Systems". Processes 10, n. 6 (16 giugno 2022): 1197. http://dx.doi.org/10.3390/pr10061197.

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The master oscillator power amplifier (MOPA) pulsed laser, one of the popular topologies for high-power fiber laser systems, is widely applied in industrial machining laser systems. In MOPA, the low-power pulsed laser, stimulated from a seed laser diode, is amplified by the high- power optical energy from pump laser diodes via the gain fiber. Generally, the high-power pump laser diodes are driven by lossy linear current drivers. The switched mode current drivers boost the driver efficiency but suffer from pulse energy consistency due to the current switching ripple. In this paper, a laser driver system that varies the switching frequency of current source to synchronize with pulsed laser repetition rate is analyzed and implemented. Experimental results are demonstrated using a 20 W pulsed fiber laser system.

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Priputnev P. V., Romanchenko I. V. e Rostov V. V. "Systems and technologies based on nonlinear transmission lines with ferrite (Review)". Technical Physics 68, n. 5 (2023): 555. http://dx.doi.org/10.21883/tp.2023.05.56060.230-22.

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Nonlinear transmission lines with ferrite have been actively developed and studied for about two decades. At the same time, the first works on this topic date back to the middle of the last century. Nonlinear transmission lines with ferrite find their application in various problems of electrophysics, with the greatest application being found in the problems of pulse sharpening, as delay lines and generators of high-power pulses of microwave radiation. The main scientific and technical results of the development of technologies of nonlinear transmission lines with ferrite are presented in chronological order, starting from lines for sharpening the fronts of voltage pulses, ending with multichannel microwave sources based on them. Keywords: high power microwaves, ferromagnetic materials, pulsed power, electromagnetic shock waves.

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Rung, Stefan, Niklas Häcker e Ralf Hellmann. "Thermal imaging of high power ultrashort pulse laser ablation of alumina towards temperature optimized micro machining strategies". IOP Conference Series: Materials Science and Engineering 1135, n. 1 (1 novembre 2021): 012027. http://dx.doi.org/10.1088/1757-899x/1135/1/012027.

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Abstract The application of pulsed laser systems with pulse durations in the pico- and femtosecond regime for material processing is commonly associated with a cold ablation. Due to the minimized interaction-time between the ultrashort laser pulses and the material, this statement is almost valid as long as no heat accumulation effect appears. With the increasing demand of high productivity processes, the average power of ultrashort pulsed laser systems increases above 100 W, which leads, however, to increased thermal effects during laser processing. This is especially important for laser processing of technical ceramics like alumina. Large temperatures gradients, which locally occur during laser processing using high average power could lead to thermal modifications and cracks in the material. In this study, we present a process-optimization method for high power laser ablation of alumina based on thermal imaging. The use of a 2D IR camera enables the estimation of the temperature distribution during the laser processing. We investigate the influence of laser power up to 80 W, pulse duration between 900 fs and 10 ps and processing duration on the resulting material temperature. Beside the material temperature we evaluate the material removal rate and the resulting surface quality.

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Li, Hongda, Bo Zhang, Sergey Sosnovskiy, Long Che, Guimao Zhang, Shuaishuai Liu e Zhao Jin. "Study of Bipolar Inductively Isolated High-Voltage Pulse Source". Electronics 12, n. 18 (13 settembre 2023): 3864. http://dx.doi.org/10.3390/electronics12183864.

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To meet the application requirements of pulsed power technology in wastewater treatment and other aspects (for example, a scenario that requires a high-voltage pulse source that can output a pulse with a rising edge in the nanosecond range and a device that can stabilize the pulse under high-frequency conditions), this paper designed an inductively isolated bipolar high-voltage pulse source. It consists of three parts: the primary charging power supply, the isolated driver circuit, and the pulse-forming circuit. By using inductance instead of traditional resistance isolation, using the inductance for charging and isolation, the inductance can increase the charging voltage of the capacitor, so the circuit can achieve a higher voltage output. The dual-Marx generator parallel connection design of the pulsed power supply topology, using a primary charging power supply for positive and negative polarity charging, can simultaneously output the reverse polarity and size of high-voltage pulses to achieve a bipolar output, so the load has an effect on the pulse. The equipment was selected on the basis of the design of the isolated driver circuit, primary charging power supply circuit, and pulse-forming circuit for the corresponding simulation, and in the experiment to build a principle model, the tests showed that the pulse source output pulse amplitude range was 0~10 kV (the positive pulse voltage was 5 kV, and the negative pulse voltage was −5 kV), the pulse rising edge was approximately 200 ns, the pulse width was 1 μs, and the frequency range was 0~1 kHz for the pulse source frequency. The power supply was designed to be used in applications such as wastewater treatment.

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Singh, S. K., J. H. Murphy, P. W. Eckels, C. J. Mole, A. T. Male e C. K. Jones. "Impact of high temperature superconductors on pulsed power systems". IEEE Transactions on Magnetics 25, n. 2 (marzo 1989): 1787–90. http://dx.doi.org/10.1109/20.92648.

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Jackel, S., M. Givon, A. Ludmirsky, S. Eliezer, J. L. Borowitz, B. Arad, A. Zigler e Y. Gazit. "Multiple-pass amplifiers for high-power laser systems". Laser and Particle Beams 5, n. 1 (febbraio 1987): 115–24. http://dx.doi.org/10.1017/s0263034600002536.

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Multiple-pass amplifiers were configured from Nd:glass rods using polarization and angular coupling techniques. Very high gain (>600) single beam triple-pass booster stages and high gain (30 or 15) single or double-beam double-pass amplifiers were combined to construct a very cost effective high-power (50 GW) pulsed laser system. These techniques were also effectively applied to smaller compact high repetition-rate systems.

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OGUNNIYI, ADERINTO, e HEATHER O'BRIEN. "PULSE EVALUATION AND RELIABILITY ANALYSIS OF 4H-SiC SGTO MODULES". International Journal of High Speed Electronics and Systems 20, n. 03 (settembre 2011): 441–55. http://dx.doi.org/10.1142/s0129156411006738.

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Army applications require power components that are utilized in pulsed power systems to be reliable and durable, compact, have high power and energy density, and lastly, to be easily integrated into combat vehicles. The U.S. Army Research Laboratory (ARL) is currently investigating silicon carbide Super-gate turn-off thyristors ( SiC SGTOs) to meet the future pulsed power system requirements for the Army. ARL's methodology is to evaluate the device performance in pulsed power circuits that emulate the electrical stresses that the power devices would encounter in a pulsed power system. Each module being evaluated utilized four 0.6 cm2 SiC SGTOs. The packaging design for the module utilizes ThinPak technology. The module has reliably been pulsed over 2000 times at peak currents greater than 8 kA with a pulse width of 170 μs. The module has also been pulsed greater than 3.6 kA at a pulse width of 1 ms, corresponding to an action rate of 7000 A2s and a current density of 2.5 kA/cm2 over the cathode mesa area. This work evaluates SiC SGTO modules under various pulsed conditions. This paper includes details on device structure, module package design, and module pulsed switching and reliability.

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Butkus, Paulius, Sonata Tolvaišienė e Sebastjanas Kurčevskis. "Validation of a SPICE Model for High Frequency Electroporation Systems". Electronics 8, n. 6 (23 giugno 2019): 710. http://dx.doi.org/10.3390/electronics8060710.

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In this paper, we present an analysis and a validation of a simulation program with integrated circuit emphasis (SPICE) model for a pulse forming circuit of a high frequency electroporation system, which can deliver square-wave sub-microsecond (100–900 ns) electric field pulses. The developed SPICE model is suggested for use in evaluation of transient processes that occur due to high frequency operations in prototype systems. A controlled crowbar circuit was implemented to support a variety of biological loads and to ensure a constant electric pulse rise and fall time during electroporation to be independent of the applied buffer bioimpedance. The SPICE model was validated via a comparison of the simulation and experimental results obtained from the already existing prototype system. The SPICE model results were in good agreement with the experimental results, and the model complexity was found to be sufficient for analysis of transient processes. As result, the proposed SPICE model can be useful for evaluation and compensation of transient processes in sub-microsecond pulsed power set-ups during the development of new prototypes.

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Susoeff, A. R., R. S. Hawke e K. S. Leighton. "A mechanical connector design for high-current, high-Coulomb pulsed power systems". IEEE Transactions on Magnetics 29, n. 1 (gennaio 1993): 1070–75. http://dx.doi.org/10.1109/20.195729.

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Zhang, Keran, Yun Hao, Shu Zhang, Yangtao Fan e Xiangyong He. "HEMP Protection of Power Systems in Electromagnetic Shielding Cabinet". Journal of Physics: Conference Series 2615, n. 1 (1 ottobre 2023): 012018. http://dx.doi.org/10.1088/1742-6596/2615/1/012018.

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Abstract High-altitude Electromagnetic Pulse (HEMP) has a significant impact on power systems. This paper simulates the HEMP coupling for three types of power cables in an electromagnetic shielding cabinet. Besides, this paper proposes the HEMP protection circuit design for 220 V AC and 24 V DC power. In a lightning conduction injection test, the circuit reduces the peak voltage by 12.1 and 14.2 times for AC and DC, respectively. In a pulsed current injection (PCI) test, the circuit reduces the transient peak current to less than 8.2 A for both AC and DC.

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Godun, D. V., S. V. Bordusau e G. P. Budzko. "Output Current Control System of a High Voltage Electric Pulse Generator for Plasma Excitation". PLASMA PHYSICS AND TECHNOLOGY 6, n. 1 (2019): 7–9. http://dx.doi.org/10.14311/ppt.2019.1.7.

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A control and pulse discharge current limiting system integrated into an AC/DC converter and pulse modulator of a high voltage pulse generator have been developed. The peculiarity of such system\textquotesingle s operation is the stabilization of the power supplied to the discharge and the correction of the width of output electric pulses towards decrease upon reaching the specified pulsed current amplitude value. The system enables the pulse generator to work in the modes close to the ``short circuited load'' mode. In this case the driving module of a composite IGBT key performs the correction of the working pulse width and blocks the pulse generator operation if needed. The suggested circuit design solutions allow using the generator in a wide range of electric plasma-forming parameters' modes and working with various types of vacuum gas discharge systems.

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Aladov, A. V., A. E. Chernyakov, A. E. Ivanov e A. L. Zakgeim. "Study of power limitation of AlGaInN LEDs in pulse regime at high current". Journal of Physics: Conference Series 2103, n. 1 (1 novembre 2021): 012186. http://dx.doi.org/10.1088/1742-6596/2103/1/012186.

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Abstract LEDs operating under high pulsed current are of a great interest for different applications, in particular, for VLC (LiFi) systems and laser pumping. Current dependences of the efficiency and emission spectra as well as the rise and fall times of high-power blue LEDs were investigated under extremely high pulse current density up to 7 kA/cm2 and pulse duration from 100 ns to 3 μs. Analysis of the pulse behaviour of the LEDs reveals that the main droop in the efficiency and change in spectra occur up to the current densities ~ 1 kA/cm2 and seems to be non-thermal.

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Radhika, G., K. Sashidhar, P. Aravinda Sai Krishna e C. Avaneesh. "Flexible output pattern high-power pulse generator". E3S Web of Conferences 472 (2024): 01016. http://dx.doi.org/10.1051/e3sconf/202447201016.

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Day by day, the need for renewable fuel has increased to reduce the usage of non-renewable fuels and also to provide adequate fuel for vehicle use worldwide. Organic fuels that can be derived from different sources are renewable fuels, of which oil extracted from algae cells can also be used as a biofuel. Algae oil extraction can be achieved by applying a Pulsed Electric Field across the algae cell to rupture its membrane and to remove oil. A Pulse Generator, capable of carrying out this operation, although in existence, has some drawbacks including lack of versatility, performance and reliability, etc. Pulse generators can also be used for many other purposes, including cancer cell ablation, water treatment, thunder and lightning safety testing of electrical equipment, lasers, radar systems, military, etc. Hence a Pulse generator capable of generating the necessary Pulse patterns, maintaining a reasonable efficiency and performance, including features such as versatility, simple input voltage stepping, high switching frequency etc. The design of a novel solid-state-based topology with the required features is considered to be the main objective of this work. In this paper, we aim to present the design and simulation of the proposed circuit, along with some results obtained.

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Grover, Harpreet Singh, e Francis Dawson. "Minimizing Late Currents in Pulsed Power Gas Laser Systems". IEEE Transactions on Plasma Science 49, n. 9 (settembre 2021): 2946–53. http://dx.doi.org/10.1109/tps.2021.3098759.

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Jian Yun, Jian Yun, Cunxiao Gao Cunxiao Gao, Shaolan Zhu Shaolan Zhu, Chuandong Sun Chuandong Sun, Haodong He Haodong He, Li Feng Li Feng, Lijun Dong Lijun Dong e Linquan Niu Linquan Niu. "High-peak-power, single-mode, nanosecond pulsed, all-fiber laser for high resolution 3D imaging LIDAR system". Chinese Optics Letters 10, n. 12 (2012): 121402–4. http://dx.doi.org/10.3788/col201210.121402.

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Kim, A. A., B. M. Kovalchuk, V. A. Kokshenev, A. V. Shishlov, N. A. Ratakhin, V. I. Oreshkin, V. V. Rostov, V. I. Koshelev e V. F. Losev. "Review of high-power pulsed systems at the Institute of High Current Electronics". Matter and Radiation at Extremes 1, n. 4 (luglio 2016): 201–6. http://dx.doi.org/10.1016/j.mre.2016.08.001.

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Krymsky, Valerii, Nataliya Shaburova e Ekaterina Litvinova. "Analysis of the Results of Pulsed Processing of Melts". Metals 10, n. 2 (1 febbraio 2020): 205. http://dx.doi.org/10.3390/met10020205.

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The paper presents the results of a relatively new method of external action on melts developed by the authors. The essence of the technology is the impact on melts before casting with electromagnetic pulses (EMP) of short duration (1 ns) and with high pulse power (2 kW). To create electromagnetic pulses, a generator with the following characteristics was used: pulse amplitude of 10 kV, the leading edge of the pulse was 0.1 ns, pulse duration of 1 ns, pulse repetition rate at 1 kHz, and a calculated pulse power of 2 MW. A distinctive feature of the generator used was its low power consumption of 50 Watts. The results of processing low-melting melts of the Al–50Pb, Bi–38Pb, and Bi–18Sn–32Pb systems presented in the work indicated that EMP treatment led to the occurrence of equilibrium crystallization of the metal, increasing its density. In addition to the experimental results, a theory is provided to explain the mechanism of the influence of pulse processing on the properties of metals of these and other systems previously studied by the authors.

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Wu, Da Yong, e Sheng Bao Yu. "Research and Implementation of the Triangular Wave Pulse Power Device". Applied Mechanics and Materials 241-244 (dicembre 2012): 657–60. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.657.

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The pulsed power is an important part of the airborne geophysical method detection systems. However, the traditional method of aerial transient electromagnetic transmitted waveform will cause the interference which is not conducive to process the post-data. The paper presents a new kind of dual polarity triangle pulse power device. The experimental results verify the correctness of theoretical analysis by using constant voltage clamping method to achieve emission of the isosceles triangular current pulse. Its falling edge of high linearity, high reliability, the output characteristics of a good anti-interference ability.

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Kondratenko, I. P., A. N. Karlov e R. S. Kryshchuk. "CONTROL STRATEGIES TO ELIMINATE HARMONICS IN POWER GENERATION SYSTEMS BASED ON A DOUBLY-FED INDUCTION GENERATOR". Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini, n. 61 (25 maggio 2022): 5–12. http://dx.doi.org/10.15407/publishing2022.61.005.

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The action of high-density pulsed currents (109 A/m2) leads to the appearance of the electro-plastic effect in metal products. It is proposed to use magnetic pulse treatment of nonmagnetic plates by electromagnetic inductors with a U-shaped magnetic circuit for local flow pulsed currents in the nonmagnetic plates. The work aims to establish an influence of a ferromagnetic platform with nonlinear magnetic permeability on pulsed eddy currents and magnetic pressure of nonmagnetic metal plates with different electrical conductivity in modeling magnetic pulse treatment of welded joints to achieve the electro-plastic effect. Numerical simulation of pulsed electromagnetic fields by the finite element method is used. The current calculation in the inductor's winding is performed by solving the equations of the magnetic field and the electric circuit equations for a discrete-time interval. A power source is a capacitor that is charged to a specific voltage. To study the effect of the ferromagnetic platform on eddy currents and forces in a nonmagnetic plate with its different electrical conductivity, the same pulsed current in the inductor's winding is used. The dependence of amplitude values of eddy current density and magnetic pressure on the surfaces of nonmagnetic plates of different electrical conductivity is investigated. The influence of the presence and absence of a ferromagnetic platform and its electrical conductivity and magnetic permeability on the values of eddy currents and magnetic pressure in the nonmagnetic plate have been studied. Ref. 13, fig. 7, table.

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Chvykov, Vladimir. "Ti:Sa Crystals in Ultra-High Peak and Average Power Laser Systems". Crystals 11, n. 7 (20 luglio 2021): 841. http://dx.doi.org/10.3390/cryst11070841.

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In this paper, Ti:Sa amplifiers with crystals of the different geometries are discussed. Benefits of using this active medium for a thin disk (TD) and slab amplifiers are evaluated numerically and tested experimentally. Thermal management for amplifiers with multi-kW average power and multi-J pulse energy has been demonstrated. The presented numerical simulations revealed the existing limitations for heat extraction in TD geometry in the sub-joule energy regime for higher repetition rate operation. Geometry conversion from TD to thin-slab (TS) and cross-thin-slab (XTS) configurations significantly increases the cooling efficiency with an acceptable crystal temperature for pump average power values up to few kW with room temperature cooling, and up to tens of kW with cryogenic cooling. The abilities to attain 0.3 J output energy and a greater than 50% extraction efficiency were demonstrated with a repetition rate exceeding 10 kHz with room temperature cooling and one order more of a repetition rate with cryogenic conditions with pulsed pumping. Direct diode pumping simulated for CW regimes demonstrated 1.4 kW output power with 34% extraction efficiency using room temperature cooling and more than 10 kW and ~40% efficiency with cryogenic cooling.

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Tikhomirov, S. A. "Femtosecond System with Pulse Pumping of Seed Laser and Amplifier by Using a Single Power Unit". Devices and Methods of Measurements 12, n. 1 (19 marzo 2021): 23–29. http://dx.doi.org/10.21122/2220-9506-2021-12-1-23-29.

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For several decades development of methods for generating ultrashort pulses has been an independent urgent scientific and technical problem. There is a constant improvement both in the methods of such pulses receiving and in methods of their use. The aim of this work was to investigate the possibility of realizing the coordinated operation of two fundamentally different types of pump lasers for the femtosecond oscillator and amplifier based on one single-lamp laser head and to create on this basis a compact high-power femtosecond system with pulsed pumping and one power unit.The practical implementation of two types of pulsed lasers (nano- and picosecond ones operating, respectively, in Q-switch and modelock regime) on a single laser head with two active elements and one pump lamp is carried out. The required synchronization in time the pump pulse femtosecond amplifier formation and quasi-stationary region of generated pulses in the output radiation of a femtosecond Ti:sapphire is obtained.On this basis a compact, pulse pumped monoblock laser system has been developed that can generate femtosecond pulses with a duration of 50–150 fs with an energy up to 1 mJ and a high enough pulse repetition rate (up to 1 kHz which is determined by the type of laser head and pump unit used). In the developed laser system a compact scheme of a stretcher-compressor with a single common diffraction grating is used.Laser systems of this type characterized by a relatively low cost due to the use of a single power supply unit for simultaneous pumping of the amplifier and oscillator, as well as lower requirements for the quality of optical elements and usage conditions due to the pulse mode of operation, are quite practical and can be used both in scientific research in the field of ultra-high-speed kinetic spectroscopy and nonlinear optics, as well as in numerous technical applications, particular in the precision processing of materials, as optical simulators of the action of heavy charged particles in testing the radiation resistance of integrated circuits and electronic modules.

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Singh, Ranbir. "HIGH POWER SIC PIN RECTIFIERS". International Journal of High Speed Electronics and Systems 15, n. 04 (dicembre 2005): 867–98. http://dx.doi.org/10.1142/s0129156405003442.

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High voltage PiN rectifiers made using conventional semiconductor materials such as Silicon are restricted to less than 20 kHz and less 120°C operation, thereby severely limiting the availability of advanced electronic hardware used for power grid (also called electric utility), energy storage, pulsed power, intelligent machinery and ultra high voltage solid state power conditioning. Such applications require high power density, very high frequency, and high temperature rectifiers to realize reasonably sized systems. SiC PiN Rectifiers are expected to play an enabling role in a variety of such high voltage applications because they have been shown to offer 2 to 3 orders of magnitude faster switching, high junction temperature capability, high current density operation, and much higher power densities as compared to Silicon.

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Li, Li, Lin Li, Huiwu Xu, Lihua Yan, Gang Li, Dapeng Wang, Jiaju Ying e Fuyu Huang. "Designing a 1550 nm Pulsed Semiconductor Laser-Emission Module Based on a Multiquantum-Well Equivalent Circuit Model". Electronics 12, n. 7 (27 marzo 2023): 1578. http://dx.doi.org/10.3390/electronics12071578.

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The demand for eye-safe 1550 nm pulsed semiconductor laser-emission modules is increasing in the field of active laser detection, owing to their long range and high precision. The high power and narrow pulse of these modules can significantly improve the distance and accuracy of active-laser detection. Here, we propose an equivalent circuit model of a multiquantum-well laser based on the structure of a laser device. We developed a design method for 1550 nm pulsed semiconductor laser-emission modules according to the equivalent circuit model of an InGaAlAs laser. In this method, the module design was divided into laser chip and laser-driver levels for optimization and simulation. At the chip level, a high-output power laser chip with optimal cavity length and optical facet coating coefficients was obtained. At the laser-driver level, the model was applied to a drive circuit to provide direct narrow optical pulses. Finally, a laser-emission module was fabricated based on the optimal design results. In addition to the power-current features of the actual laser, the critical voltage of the emission module and laser pulses were tested. By comparing the test and simulation results, the effectiveness of the proposed method was confirmed.

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Żbik, Mateusz, e Piotr Wieczorek. "Charge-Line Dual-FET High-Repetition-Rate Pulsed Laser Driver". Applied Sciences 9, n. 7 (27 marzo 2019): 1289. http://dx.doi.org/10.3390/app9071289.

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Most modern pulsed laser systems require versatile laser diode drivers. A state-of-the-art pulsed laser driver should provide precise peak power regulation, high repetition rate, and pulse duration control. A new, charge line dual-FET transistor circuit structure was developed to provide all these features. The pulsed modulation current is adjustable up to Imax = 1.2 A, with the laser diode forward voltage acceptable up to UF max = 20 V. The maximum repetition rate is limited by a charge line circuit to frep max = 20 MHz. Compared to the conventional single transistor drivers, the solution proposed in this paper allows a precise, high resolution width regulation to be obtained, whereas a low pulse jitter is ensured. In the solution, two separate, out-of-phase signals are used to trigger the individual Field Effect Transistors (FET). The resultant pulsed modulation current full-width-at-half-maxima (FWHM) is regulated from ~200 ps up to 2 ns. All control and timing signals are generated with a popular Field-Programmable Gate Array (FPGA) digital circuitry. The use of standard FPGA devices ensures the low cost and high reliability of the circuit, which are not available in laser drivers consisting of sophisticated analogue adjustable delay circuits.

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Schille, Joerg, Sebastian Kraft, Theo Pflug, Christian Scholz, Maurice Clair, Alexander Horn e Udo Loeschner. "Study on X-ray Emission Using Ultrashort Pulsed Lasers in Materials Processing". Materials 14, n. 16 (12 agosto 2021): 4537. http://dx.doi.org/10.3390/ma14164537.

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The interaction of ultrashort pulsed laser radiation with intensities of 1013 W cm−2 and above with materials often results in an unexpected high X-ray photon flux. It has been shown so far, on the one hand, that X-ray photon emissions increase proportionally with higher laser power and the accumulated X-ray dose rates can cause serious health risks for the laser operators. On the other hand, there is clear evidence that little variations of the operational conditions can considerably affect the spectral X-ray photon flux and X-ray emissions dose. In order to enhance the knowledge in this field, four ultrashort pulse laser systems for providing different complementary beam characteristics were employed in this study on laser-induced X-ray emissions, including peak intensities between 8 × 1012 W∙cm−2 < I0 < 5.2 × 1016 W∙cm−2, up to 72.2 W average laser power as well as burst/bi-burst processing mode. By the example of AISI 304 stainless steel, it was verified that X-ray emission dose rates as high as H˙′ (0.07) > 45 mSv h−1 can be produced when low-intensity ultrashort pulses irradiate at a small 1 µm intra-line pulse distance during laser beam scanning and megahertz pulse repetition frequencies. For burst and bi-burst pulses, the second intra-burst pulse was found to significantly enhance the X-ray emission potentially induced by laser pulse and plasma interaction.

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Majernik, Nathan, Walter Lynn, Yusuke Sakai e James Rosenzweig. "Plasma Deflection Interrupter for Pulsed Power Applications". Instruments 2, n. 3 (29 luglio 2018): 14. http://dx.doi.org/10.3390/instruments2030014.

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A plasma-based opening switch, capable of handling kiloampere currents at kilovolt potentials on the microsecond timescale, is described and characterized. The principle of operation is the deflection of a laser-induced arc by an external magnetic field to a shunt circuit path. A first-order model of operation is introduced. Finally, the merits of the device, particularly when applied to high-repetition-rate dense plasma focus (DPF) systems, are discussed.

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Guo, Huaixin, Tangsheng Chen e Shang Shi. "Transient Simulation for the Thermal Design Optimization of Pulse Operated AlGaN/GaN HEMTs". Micromachines 11, n. 1 (9 gennaio 2020): 76. http://dx.doi.org/10.3390/mi11010076.

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The thermal management and channel temperature evaluation of GaN power amplifiers are indispensable issues in engineering field. The transient thermal characteristics of pulse operated AlGaN/GaN high electron mobility transistors (HEMT) used in high power amplifiers are systematically investigated by using three-dimensional simulation with the finite element method. To improve the calculation accuracy, the nonlinear thermal conductivities and near-junction region of GaN chip are considered and treated appropriately in our numerical analysis. The periodic transient pulses temperature and temperature distribution are analyzed to estimate thermal response when GaN amplifiers are operating in pulsed mode with kilowatt-level power, and the relationships between channel temperatures and pulse width, gate structures, and power density of GaN device are analyzed. Results indicate that the maximal channel temperature and thermal impedance of device are considerably influenced by pulse width and power density effects, but the changes of gate fingers and gate width have no effect on channel temperature when the total gate width and active area are kept constant. Finally, the transient thermal response of GaN amplifier is measured using IR thermal photogrammetry, and the correctness and validation of the simulation model is verified. The study of transient simulation is demonstrated necessary for optimal designs of pulse-operated AlGaN/GaN HEMTs.

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Anagha, A. P., e K. Sunitha. "Influence of Field Spacer Geometry on the Performance of a High Voltage Coaxial Type Transmission Line with Solid Dielectric Spacer in Vacuum". Engineering, Technology & Applied Science Research 7, n. 3 (12 giugno 2017): 1605–10. http://dx.doi.org/10.48084/etasr.1188.

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With the development of more powerful high power electromagnetic sources, the transmission of high voltage power particularly between pulsed power systems to huge power rated microwave sources in absence of electrical breakdown and pulse distortion has begun to become a vital issue. A high voltage coaxial type transmission line with 500 kV peak voltage in vacuum is proposed. A novel proposal of configuration bearing a positive angle of 45o with socket-type filed shaper is being discussed in this paper in a manner to improve surface flashover properties and also to decrease the distortion seen in the pulse shape. This type of transmission line provides high capability of hold off voltage. The electric field distribution of the coaxial geometry with different field shaper configurations and different spacer parameters are also investigated using COMSOL software.

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32

Coroado, Julio, Supriyo Ganguly, Wojciech Suder, Stewart Williams, Sonia Meco e Goncalo Pardal. "Selection of parameters in nanosecond pulsed wave laser micro-welding". International Journal of Advanced Manufacturing Technology 115, n. 9-10 (31 maggio 2021): 2929–44. http://dx.doi.org/10.1007/s00170-021-07251-8.

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AbstractThe digital control of the latest nanosecond pulsed wave (PW) fibre lasers allows very high flexibility in controlling the application of the total energy to a workpiece, which brings several advantages to the joining process. By choosing different pulse shapes in different spatial profiles, it is possible to apply low energy per pulse with high precision and accuracy resulting in lower heat input. Since the energy of each pulse is insufficient to generate melting, these lasers operate at very high pulse repetition frequencies near continuous wave (CW) regime. Nevertheless, the peak powers of PW lasers are much higher than CW. In this research, the effect of peak power, pulse energy, pulse width, pulse repetition frequency and duty cycle has been studied. The experimental work was conducted in bead on plate of austenitic stainless steel to investigate the effect of laser on the weld geometry, i.e. depth of penetration and width. An empirical model, previously established for CW mode, which enables the achievement of a particular penetration depth independent of the beam diameter, was redesigned and tested for PW mode. The “pulse power factor model” allows the laser user to select a weld profile that meets certain quality and productivity requirements independent of the laser system. It was shown that identical depth of penetration but different weld metal profile can be obtained for a specific beam diameter for a range of different system parameters by keeping a constant trade-off between pulse power factor and interaction time.

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DÖRR, M., D. ECKERT, H. ESCHRIG, F. FISCHER, P. FULDE, R. GROESSINGER, W. GRÜNBERGER et al. "THE DRESDEN 100 T/10 ms PROJECT: A HIGH MAGNETIC FIELD FACILITY AT AN IR-FEL". International Journal of Modern Physics B 16, n. 20n22 (30 agosto 2002): 3397. http://dx.doi.org/10.1142/s0217979202014541.

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We have proposed to build a 100 T/10 ms, 70 T/100 ms, 60 T/1 s pulsed field user facility with a 50 MJ capacitor bank at the Forschungszentrum Rossendorf near Dresden. This would provide the appealing possibility to have access to Zeeman energies in the energy range of the infrared free-electron-lasers (5 μm to 150 μm; 2 ps; cw; > 10 W) now under construction at the radiation source ELBE (superconducting electron linear accelerator; 40 MeV; 1 mA; 2 ps; cw) in Rossendorf. The work is accompanied by computer simulations of the planned coil systems, of the power supply, and by the development of high-strength conductors aiming at a tensile strength of about 1.5 GPa at σ ≈ σ Cu/2 (microcomposite CuAg alloys and Cu-steel macro compounds). With a view of gaining experience in the construction and operation of pulsed magnets, a pilot pulsed field laboratory was established at the Institute of Solid State and Materials Research Dresden (IFW Dresden). The laboratory includes short pulse magnets with peak field up to 60 T in a 24 mm bore and a rise time of about 10 ms (coil from NHMFL, Tallahassee), and a 40 T long pulse magnet with 24 mm bore and rise time of about 80 ms (coil from METIS, Leuven). The repetition rate of 20 min between pulses is limited by the cooling time of the coils. The coils are energized by a 1 MJ, 10 kV capacitor bank with some special features. With this set-up measurements of magnetization and magnetotransport on 4f-electron systems, for example RECu2, have been out in the temperature range of 1.5 to 300 K and at fields up to 52 T using high precision pick-up coils.

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Nagarajan, P., N. Ashok Kumar e P. Venkat Ramana. "Design of implicit pulsed-dual edge triggering flip flop for low power and high speed clocking systems". International Journal of Wavelets, Multiresolution and Information Processing 18, n. 01 (11 giugno 2019): 1941009. http://dx.doi.org/10.1142/s0219691319410091.

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The flip-flops are considered as major contributors to the power dissipation of the clocking system, which is made up of the clock provision network and storage elements (latches, flip-flops). The power- and delay-efficient new implicit-pulsed dual-edge triggering flip-flop circuit (IP-DETFF) is proposed with two latching stages by employing an implicit-pulse triggering, dual-edge clocking and reducing the number of clocked loads. This leads to the reduction of power consumption due to clock allocation tree (pclk-tree) and reduces the delay time. The dual-edge clocking technique is incorporated into this proposed design without an increment of the number of transistors and minimizes the operating frequency as half. This methodology is also employed in this proposed design to construct new latching part of the flip-flop circuit. The performance of proposed flip-flop is analyzed by simulating the circuit at 0.12[Formula: see text][Formula: see text]m CMOS (complementary metal oxide semiconductor) process technology. The simulation results show that the proposed design achieves power saving from 11.22% to 54.81%, improvement of speed from 67% to 71.50%, power-delay product (PDP) from 74.85% to 81.26 %, energy-delay product (EDP) from 87.86% to 92.4% and power-energy product (PEP) from 75.24% to 93.57% compared to the conventional flip-flops.

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35

Moffett, Mark B., David L. Chesny, Jake M. Cole, Kaleb W. Hatfield e Razvan Rusovici. "Bdot probe and Rogowski coil cross-calibration and sensor fusion in pulsed direct current capacitor discharges". Review of Scientific Instruments 93, n. 3 (1 marzo 2022): 034707. http://dx.doi.org/10.1063/5.0076741.

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Abstract (sommario):

Bdot probes and Rogowski coils are used in the measurement of transient magnetic fields and currents, respectively. They both share the mechanism of creating an induced electromotive force response via Faraday’s law, which scales linearly with the pulsed magnetic field. High power capacitor direct current (DC) discharge systems release a single pulse of current that is both very high and very fast (≲1 ms). To capture these transient data and characterize these systems, high current tolerant and fast response time sensors are required. While these measuring devices have been well studied and utilized for almost 100 years, a comprehensive and detailed description of the custom design, calibration, and sensor fusion application of these tools for use in various pulsed DC capacitor value discharges is largely missing in the literature. Using robust analytical calculations, finite element analyses, and empirical methods, we have developed a sensor fusion protocol for current and magnetic field probes (with relative errors of ±13% and ±15%, respectively) for use in any geometry of high speed pulsed DC current calibrated capacitor discharge systems. This paper comprehensively outlines the design and sensor fusion methodologies that allow for the deployment of in-house built Bdot probes and Rogowski coils to a wide range of pulsed DC systems and demonstrates their use in a characteristic plasma environment.

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36

Sumathy, P., J. Divya Navamani, A. Lavanya, Jagabar Sathik, R. Zahira e Fadl A. Essa. "PV Powered High Voltage Pulse Converter with Switching Cells for Food Processing Application". Energies 16, n. 2 (16 gennaio 2023): 1010. http://dx.doi.org/10.3390/en16021010.

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Abstract (sommario):

In recent years, industries in the suburb have retrofitted their power supply units with solar power supply systems. Using solar power supply systems for various applications, such as food processing, enables energy expense saving. A promising opportunity in the food industry is solar-powered Pulsed Electric Field (PEF) used in the treatment of fruits and their by-products. For this application, a converter is proposed in this paper with a combination of a passive switched inductor cell and a switched capacitor cell. Furthermore, the derived topology possesses an extendable feature. This topology generates high voltage repetitive pulses with a single semiconductor switch and a reduced component count. Dynamic study of the converter is also performed with the derivation of the transfer function. Cost effective, reliable, and simple circuitry are the critical features of this topology. The circuit topology can generate high voltage pulses by increasing the number of switched inductors and switched capacitor cells. A correlation study on the impact of the switched inductor/capacitor cell is also performed and analyzed, which is not usually performed. A 50 W prototype is designed and tested to validate the performance of the converter

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37

Malviya, Devesh, e Mummadi Veerachary. "A Boost Converter-Based High-Voltage Pulsed-Power Supply". IEEE Transactions on Industry Applications 56, n. 5 (settembre 2020): 5222–33. http://dx.doi.org/10.1109/tia.2020.3007396.

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38

Gaida, Christian, Fabian Stutzki, Florian Jansen, Hans-Jürgen Otto, Tino Eidam, Cesar Jauregui, Oliver de Vries, Jens Limpert e Andreas Tünnermann. "Triple-clad large-pitch fibers for compact high-power pulsed fiber laser systems". Optics Letters 39, n. 2 (3 gennaio 2014): 209. http://dx.doi.org/10.1364/ol.39.000209.

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39

May, M. J., T. Clancy, D. Fittinghoff, C. Halvorson, T. Mills, A. Nikitin, T. Perry et al. "High bandwidth data recording systems for pulsed power and laser produced plasma experiments". Review of Scientific Instruments 77, n. 10 (ottobre 2006): 10F504. http://dx.doi.org/10.1063/1.2219417.

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40

Hua Bai, Zhengming Zhao e C. Mi. "Framework and Research Methodology of Short-Timescale Pulsed Power Phenomena in High-Voltage and High-Power Converters". IEEE Transactions on Industrial Electronics 56, n. 3 (marzo 2009): 805–16. http://dx.doi.org/10.1109/tie.2008.2004387.

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41

Fu, Chao, Wenrao Fang, Ruyu Fan, Lulu Wang, Wenhua Huang, Yuchuan Zhang e Changkun Liu. "Design and Implementation of Low Parasitic Inductance Bias Circuit for High-Power Pulsed Power Amplifiers". Electronics 12, n. 6 (17 marzo 2023): 1430. http://dx.doi.org/10.3390/electronics12061430.

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Abstract (sommario):

This article presents a wideband bias circuit with low parasitic inductance for high-power pulsed amplifiers. The proposed bias circuit works similarly to the traditional bias circuit in that it can ensure the transmission of microwaves from the power amplifier to the load while preventing the transmission of microwaves from the power amplifier to the power supply. By making the bias line shorter and the transmission line wider than the traditional bias circuit, the proposed bias circuit reduces its parasitic inductance. The reduction of parasitic parameters is critical for reducing the drain voltage overshoot of the high-power pulse power amplifier and ensuring its safety. The simulation results demonstrate that the proposed bias circuit has a lower parasitic inductance and a wider bandwidth. To validate the theory and simulation results, the traditional and the proposed bias circuits are fabricated using microstrip circuits. Both the simulation and experimental results indicate that the proposed bias circuit has a one-third lower parasitic inductance than the traditional bias circuit. Furthermore, the proposed bias circuit has a wider bandwidth.

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42

Korobkov, S. V., M. E. Gushchin, A. V. Strikovskiy, I. M. Vershinin, I. Yu Zudin, K. N. Loskutov, A. S. Nikolenko et al. "NONLINEAR PHENOMENA DURING THE PROPAGATION OF POWERFUL NANOSECOND ELECTROMAGNETIC PULSES IN A LARGE-SCALE STRIPE LINES WITH A GAS AT REDUCED PRESSURE". Доклады Российской академии наук. Физика, технические науки 510, n. 1 (1 maggio 2023): 16–21. http://dx.doi.org/10.31857/s2686740023030100.

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Abstract (sommario):

Experiments of propagation of the high-power high-voltage nanosecond and subnanosecond pulses in large-scale transmitting lines in various gases make it possible to solve a wide range of fundamental and applied problems, from simulating the propagation of electromagnetic pulses (EMP) through the atmosphere to estimating the electrical strength of elements of pulsed high-voltage gas-filled systems. At the IAP RAS, experiments with stripe lines up to 5 m in length are performed in Krot and Sprite devices. During the propagation of EMP with an electric field strength up to 100 kV/m in a low pressure gas, the effects are observed such as the formation of non-uniform and essentially non-stationary glow, nonlinear absorption and dispersion transformation of the shape of high-power pulses, due to gas ionization in the EMP field.

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Rajan, Rehim N., J. Mondal, A. R. Tillu, V. Sharma, D. Bhattacharjee, Shiv Chandan, V. Yadav e Archana Sharma. "Analysis of energy stability in 6/4 MeV dual energy RF electron linac". Journal of Instrumentation 17, n. 10 (1 ottobre 2022): P10022. http://dx.doi.org/10.1088/1748-0221/17/10/p10022.

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Abstract RF linear accelerators are used to produce high energy electron beams up to several MeV for various industrial, medical and research applications. Accelerators with switchable energy are increasingly finding application in non-destructive testing systems with material discrimination capability. These systems are based on pulsed accelerators with duration 3 to 10 micro second with repetition rate up to 400 Hz. Magnetrons are used as microwave source in relatively low power accelerator systems. This paper examines various factors affecting the pulse to pulse energy variation in such radiation sources. Contributions from individual subsystems are accounted and the cumulative performance is evaluated. Dose stability improvement with remedial measures has been discussed.

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44

Eidam, Tino, Sven Breitkopf, Oliver Herrfurth, Fabian Stutzki, Marco Kienel, Steffen Hädrich, Christian Gaida e Jens Limpert. "High-power ultrafast fiber lasers for materials processing". Advanced Optical Technologies 10, n. 4-5 (15 ottobre 2021): 277–83. http://dx.doi.org/10.1515/aot-2021-0033.

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Abstract State-of-the-art fiber-laser systems can deliver femtosecond pulses at average powers beyond the kilowatt level and multi-mJ pulse energies by employing advanced large-mode-area fiber designs, chirped-pulse amplification, and the coherent combination of parallel fiber amplifiers. By using sophisticated coherent phase control, one or even several output ports can be modulated at virtually arbitrary power levels and switching speeds. In addition, an all-fiber setup for GHz-burst generation is described allowing to access an even wider range of laser parameters. The combination of all these approaches together with the robustness, efficiency, and excellent beam quality inherent to fiber-laser technology has the potential to strongly improve existing materials-processing applications.

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Agamy, Mohammed, Fengfeng Tao e Ahmed Elasser. "High-Speed Medium-Voltage SiC Thyristors for Pulsed Power Applications". IEEE Transactions on Industry Applications 57, n. 4 (luglio 2021): 3812–21. http://dx.doi.org/10.1109/tia.2021.3069717.

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46

Haglund, Richard F. "Damage Mechanisms in Optical Materials For High-Power, Short-Wavelength Laser Systems". MRS Bulletin 11, n. 3 (giugno 1986): 46–47. http://dx.doi.org/10.1557/s088376940005483x.

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Abstract (sommario):

Damage to optical materials under intense photon irradiation has always been a major problem in the design and operation of high-energy and high-average-power lasers. In short-wavelength lasers, operating at visible and ultraviolet wavelengths, the problem appears to be especially acute; presently attainable damage thresholds seriously compromise the engineering design of laser windows and mirrors, pulsed power trains and oscillator-amplifier systems architecture. Given the present interest in ultraviolet excimer lasers and in short-pulse, high-power free-electron lasers operating at visible and shorter wavelengths, the “optical damage problem” poses a scientific and technological challenge of significantdimensions. The solution of this problem even has significant implications outside the realm of lasers, for example, in large space-borne systems (such as the Hubble Telescope) exposed to intense ultraviolet radiation.The dimensions of the problem are illustrated by the Large-Aperture krypton-fluoride laser amplifier Module (LAM) shown schematically in Figure 1. This device, now operating at the Los Alamos National Laboratory, is typical of current and planned large excimer lasers for fusion applications. The LAM has an active volume of some 2 m3, and optical surfaces (resonator mirror and windows) exceeding 1 m2 in size; the fabrication of these optical elements was the most expensive and time-consuming single item in the construction of the laser. During laser operation, a population inversion in an Ar-Kr-F2 mix ture is created through electron-beam excitation of the laser gas by two 400 kA beams of 650 keV electrons from a cold cathode discharge. The electron trajectories in the gas are constrained by a 4 kG magnetic field transverse to the optical axis produced by a pair of large Helmholtzcoils.

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Rai, Krishna Kumar, A. V. Giridhar, D. R. Jahagirdhar, Ashish Rai e Akash Kumar Paul. "Investigation on the Effect of Cable Length on Pulse Shape of High Voltage High Pulse Power Supply". Defence Science Journal 72, n. 2 (11 maggio 2022): 243–49. http://dx.doi.org/10.14429/dsj.72.17548.

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Abstract (sommario):

In the present scenario of pulse power applications, transmission of high voltage pulses varies as per load condition. In the early days of its application, High Voltage High Pulse Power Supply (HVHPPS) design saw short distance between load and source, where the effect of cable length was not taken into account for design. This paper presents the effect of cable length on pulse shape of High Voltage High Pulse Power Supply. The load under observation is Klystron based high energy particle accelerator system. The performance of pulse power systems were observed continuously on a daily basis throughout the year and detailed analysis was carried out. This paper generates the model of pulse forming system and provides details of pattern distortion of the pulse shape due to various dynamic parameter changes i.e. impedance, Load Voltage, Load Current, Cavity Dimensional Changes (Microwave components) due to temperature variations and performance of the power supply. The results were analysed and validated with hardware results across a range of actual industrial loads.

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Mocek, T., M. Divoky, M. Smrz, M. Sawicka, M. Chyla, P. Sikocinski, H. Vohnikova et al. "Status of HiLASE project: High average power pulsed DPSSL systems for research and industry". EPJ Web of Conferences 59 (2013): 08003. http://dx.doi.org/10.1051/epjconf/20135908003.

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ROSS, I. N., P. MATOUSEK, M. TOWRIE, A. J. LANGLEY, J. L. COLLIER, C. N. DANSON, C. HERNANDEZ-GOMEZ, D. NEELY e K. OSVAY. "Prospects for a multi-PW source using optical parametric chirped pulse amplifiers". Laser and Particle Beams 17, n. 2 (aprile 1999): 331–40. http://dx.doi.org/10.1017/s0263034699172203.

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Abstract (sommario):

The properties of optical parametric amplifiers are well suited to their use as chirped pulse amplifiers in short pulse high-power systems. In addition to the possibility of very simple designs to extend to shorter pulses the limits of millijoule systems, they can be used for very high-intensity applications when used in conjunction with narrow-bandwidth high-energy lasers. Powers exceeding 10 PW and focused intensities more than 1023 W/cm2 are predicted using existing glass laser technology.

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KUMAR, GYANENDRA, Sandeep Shelar, Ankur Patel, Amitava Roy, Ramanujam Sarathi, Rajshri Singh e Archana Sharma. "Investigation of Effect of Nanosecond Pulsed Electric Field on MCF-7 Breast Cancer Cells". Journal of Drug Delivery and Therapeutics 11, n. 3 (15 maggio 2021): 43–49. http://dx.doi.org/10.22270/jddt.v11i3.4827.

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Pulsed electric field therapy is a novel non-invasive approach for cancer therapy. It serves as a cell permeability enhancing agent for cancer treatment. Nanosecond, high-electrical field pulse power technology is used for delivering variable, controllable, intracellular electrical perturbations in several biological systems. Here, we investigated the effect of nanosecond (ns) electric pulse (nsEP) as a therapeutic tool for cancer. In in-vitro study, the breast cancer cells (MCF-7) were exposed with electric field of ~18kV/cm intensity, ~25ns duration, at 1.5Hz in a 2mm electroporation cuvette. Post exposure, observation shows a significant reduction in cell viability. It was evident that after treatment the viability of MCF-7 cancer cells at 630 pulses are remains ~38% only. The optical microscopic analysis of MCF-7 cells shows cell morphology changes after electrical pulse exposure. Moreover, we have also investigated a comparative study of the effect nano-second electrical pulses on MCF-7 cells and Chinese Hamster Ovary (CHO) cell line. The comparative study, demonstrated that the effect of nsEPF on MCF-7 is more destructive than on CHO cell line. The obtained results support that the pulse electrical field of nanosecond (ns) duration therapy would be a potential solution for cancer treatment. Keywords: Nanosecond Pulse Electric Field; Full Width at Half Maxima; Pulse Forming Line; Pulse Exposure; Viability;

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