2020 IEEE International Conference on Plasma Science (ICOPS)最新文献_第3页

Pulsed Laser Deposition: A Flexible Tool for the Synthesis of Advanced Functional Materials 脉冲激光沉积:一种合成先进功能材料的灵活工具

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717507

M. Chaker

{"title":"Pulsed Laser Deposition: A Flexible Tool for the Synthesis of Advanced Functional Materials","authors":"M. Chaker","doi":"10.1109/ICOPS37625.2020.9717507","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717507","url":null,"abstract":"Innovation in materials science and engineering resides in our ability to design new materials with tailored properties (electri cal, optical, magnetic, etc.) by controlling their nanostructure. One of the most powerful means to uniquely arrange matter at such scale is to use plasmas due to their unique ability to provi de simultaneously a variety of particles with different energies such as ions, neutral atoms and radicals. In this presentation, w e will focus on the synthesis of metal insulator transition (MIT) materials using the Pulsed Laser Deposition (PLD) tech nique that allows an excellent control of material stoichiometr y and density as well as of the material nanostructure. Vanadiu m dioxide (VO2) and samarium nickelate (SmNiO3) are particularly interesting MIT materials as their electrical resistivity as well as their infrared and terahertz (THz) reflectivity undergo significant changes across the thermo/photo-induced MIT, at transition temperatures TMIT ≈ 68 °C and 130 °C respectively. In a series of investigations, our group has examined the physics governing the MIT of VO2 and SmNiO3 thin films and has explored new application opportunities including uncooled bolometers, and smart radiator devices for space applications.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122225818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laser Spectroscopic Diagnosis of Active Species in Atmospheric Discharge Plasma 大气放电等离子体中活性物质的激光光谱诊断

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717506

C. Feng, Zhiwei Wang, H. Ding

{"title":"Laser Spectroscopic Diagnosis of Active Species in Atmospheric Discharge Plasma","authors":"C. Feng, Zhiwei Wang, H. Ding","doi":"10.1109/ICOPS37625.2020.9717506","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717506","url":null,"abstract":"Surface micro-discharge (SMD), one type of cold atmospheri c pressure plasmas (CAPS), promises a bright future for num erous applications spanning the fields of aerospace and biom edicine due to its desirable features. Significantly, the reactiv e chemical species are key enablers and responsible for the bi omedical effects. Of all the CAP sources under investigation, the SMD array configuration offers a large area discharge wit h a considerable discharge volume enhances the plasma unifo rmity and provides an alternative to atmospheric pressure pla sma array technologies. This work presents the transport beh avior investigation of OH as well as NO radicals in an atmos pheric pressure pulsed-modulated surface micro-discharge in helium. Laser-induced fluorescence is employed to measure t he time development of OH and NO radical density distributi on during the pulse duration and the inter-pulse period. It is s hown that convection caused by ion wind due to electro hydr odynamic force enhances and dominates the transport of OH radicals from the surface plasma layer to the afterglow region with a distance up to 8 mm away from the dielectric surface. Interestingly, after the plasma switches off, OH density decre ases quickly near the electrode but the downstream distributi on region keeps constant, showing that the impact of convecti on is still present during the post-discharge. Additionally, the propagation velocity of OH declines monotonously with time. The maximum value is estimated as 1.86 m/s during the first 1 ms when the plasma is on. The influence of power delivere d to plasma is investigated, and the results indicate that the O H density everywhere in the detection zone is directly proport ional to the applied power. However, the input power has no significant influence on the propagation velocity and delivery distance, suggesting that it is unrealistic to increase the deliv ery distance of reactive species by increasing the power deliv ered to plasma.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116722877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Attenuation of Terahertz Waves by Wet Sn Ow, Dry Snow and Rain 湿雪、干雪和雨对太赫兹波的衰减

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717532

Yasith Amarasinghe, Wei Zhang, Rui Zhang, D. Mittleman, Jianjun Ma

{"title":"Attenuation of Terahertz Waves by Wet Sn Ow, Dry Snow and Rain","authors":"Yasith Amarasinghe, Wei Zhang, Rui Zhang, D. Mittleman, Jianjun Ma","doi":"10.1109/ICOPS37625.2020.9717532","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717532","url":null,"abstract":"The technology of terahertz (THz) waves offer wide bandwidth and high capacity for future wireless communications. However, THz waves also suffer from high sensitivity to adverse weather conditions when propagating in the near-surface atmosphere. There have been several systematic studies conducted on this under different weather conditions such as rain, fog, haze, cloud and air turbulence. In particular, several investigations of the scattering performance of terahertz waves in snow have been reported [1]. But, there is still a lack of systematic studies because of the difficulties in measurements and characterizations due to the complicate shapes of snow particles. Therefore, a combined approach relying on both theoretical models and case studies is valuable. In this work, we combine meteorological data and Mie scattering theory to investigate the scattering behavior of THz waves in falling snow and in a snow layer. The theoretical results are in rough qualitative agreement with the experimental data when gaseous attenuation and scintillation effect are not considered. Compared with the attenuation by rain, the THz signal suffers higher loss when propagates in dry and wet snow for frequencies above 200 GHz. Signal loss in dry snow layer is mainly attributed to scattering effects because of the low water content, and it doesn't change when the temperature is reduced from 0 to -20 oC. The absorption effect becomes more serious when snow wetness increases, but the scattering effect is largely unaffected by water content.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129564958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rayleigh-Taylor Growth of Isolated Bubbles and Spikes in Laser-Driven Foils 激光驱动箔中孤立气泡和尖峰的瑞利-泰勒生长

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717796

A. Velikovich, C. Zulick, Y. Aglitskiy, M. Karasik, A. Schmitt, S. Obenschain

引用次数: 0

Characterization of Coupling Coefficient for Transformer Model Application in Non-Invasive Plasma Monitoring 变压器模型耦合系数表征在无创等离子体监测中的应用

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717830

Haneul Lee, Y. Jang, M. Lee, Ki-Baek Roh, Taejun Park, Ing-Fang Lee, Gon-Ho Kim

{"title":"Characterization of Coupling Coefficient for Transformer Model Application in Non-Invasive Plasma Monitoring","authors":"Haneul Lee, Y. Jang, M. Lee, Ki-Baek Roh, Taejun Park, Ing-Fang Lee, Gon-Ho Kim","doi":"10.1109/ICOPS37625.2020.9717830","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717830","url":null,"abstract":"Coupling coefficient ($k$) in transformer model, which is widely used in the circuit analysis of inductively coupled plasma(ICP) discharges, is a global value that indicates the degree of coupling by the change of magnetic flux between the primary antenna current and the secondary plasma current. Although the determinants of $k$ include the skin depth as a function of electron density and effective electron collision frequency, those plasma parameters can be calculated inversely from the relation between $k$ and electrical parameters at the antenna of ICP without additional diagnostic tools at a given pressure. In real-time non-invasive plasma diagnosis method using the determined $k$ based on the transformer model, the magnetic inductance due to the discharge current path ($L_{p}$) is assumed to be equal to the inductance of antenna ($L_{a}$) to simplify the circuit analysis model1. This study clarifies the applicable discharge condition of $L_{p}=L_{a}$ assumption in transformer model analysis by measuring voltage and current(V-I) of the antenna and plasma parameters. Difference between calculated values of $k$ from the measured antenna V-I and plasma properties in various conditions explains the possible range of $L_{p}=L_{a}$ assumption. Experiment was conducted on H-mode ICP discharge and the results are in good agreement with the predictive trends based on numerical approach of electromagnetic model. Verification of coupling coefficient in transformer model with electric signals and plasma parameters shows that monitoring of coupling coefficient can be adopted for real-time monitoring of volume averaged plasma parameter in non-invasive ICP plasma diagnostics.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129045267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Intense Relativistic Cyclotron Beams and Disk Beams for High Power Millimeter Wave Generation 高功率毫米波产生的强相对论回旋加速器束和盘束

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717625

Jun Zhang, Dian Zhang, Fangchao Dang, Xiaoping Zhang

引用次数: 0

Effect of Mutual Flux Linkage Between Stages on the Projectile Motion in a Multistage Induction Coilgun 多级感应线圈炮中级间相互磁链对弹丸运动的影响

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717494

Ranashree Ram, M. J. Thomas

{"title":"Effect of Mutual Flux Linkage Between Stages on the Projectile Motion in a Multistage Induction Coilgun","authors":"Ranashree Ram, M. J. Thomas","doi":"10.1109/ICOPS37625.2020.9717494","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717494","url":null,"abstract":"In the multistage operation of an induction coilgun, the time- varying magnetic flux generated due to the excitation of the first stage magnetically links with the coils in the subsequent stages and induces emf across their terminals. The magnetic flux linkage and the induced emf depend on the distance between the stages. This induced emf tries to circulate a current through the coils in the subsequent stages, if allowed to flow by such means of Pulsed Power Source (PPS) connection with the coils i.e., it depends on the winding direction (clockwise or anti-clockwise) of the coils and the connection of the crowbar diode in the PPS circuit. If crowbar diode is connected in parallel with the capacitor bank then the series main switch resists this induced flow of current through the coil, but if crowbar diode is connected in parallel with the coil in accordance to its winding direction then induced current flows through the coil. In this paper, the effect of this induced current on the motion of the projectile inside a multistage induction coilgun has been analyzed taking different lengths of the hollow projectile of fixed mass and outer diameter. The results of each case have then been compared with that of a single stage coilgun. Analyses have been made using the 2D transient solver of ANSOFT Maxwell software package with excitation (two 252 μF capacitors charged at 2 kV) given only for the first stage. Only two stages have been considered since farther stages will have negligible magnetic flux linkage with the first stage. For each projectile, distance between two stages has been varied starting from 2.8 cm to 14.8 cm with a linear step of 1 cm. The results show that projectile motion is slightly effected in multistage depending on the distance between stages and the length of the projectile. The results will be helpful for maintaining a suitable distance between stages in the multistage design of an induction coilgun.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129280102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Plasma Space Propulsion for Nanosatellite Orbit Control and Complex Constellation Formation 等离子体空间推进用于纳米卫星轨道控制和复杂星座形成

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717931

Shuyan Xu

引用次数: 0

Two-Stage Micro-Cathode MPD Thruster and its Improvement by the Threshold Behavior of the Magnetized ARC 两级微阴极MPD推力器及其磁化电弧阈值特性的改进

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717350

D. Zolotukhin, L. Brieda, K. Daniels, M. Keidar

引用次数: 0

Effect of RF Fields on Electrical Breakdowns Produced by High-Voltage Pulses in Air at Ambient Conditions 环境条件下射频场对空气中高压脉冲产生的击穿的影响

2020 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2020-12-06 DOI: 10.1109/ICOPS37625.2020.9717921

Roman Zamchii, D. Lacoste, J. Damazo, E. Kwon

{"title":"Effect of RF Fields on Electrical Breakdowns Produced by High-Voltage Pulses in Air at Ambient Conditions","authors":"Roman Zamchii, D. Lacoste, J. Damazo, E. Kwon","doi":"10.1109/ICOPS37625.2020.9717921","DOIUrl":"https://doi.org/10.1109/ICOPS37625.2020.9717921","url":null,"abstract":"Wireless devices are increasingly used in industry to optimize development and to reduce weight. However, various aspects of wireless device design have an effect on the potential for ignition which include the antenna/receiver's geometry, power, and operational frequency. For a safe integration of wireless devices in flammable leakage zones, a better understanding of radio frequency (RF) fields on ignition hazard is required. There are three ignition scenarios connected with the usage of wireless sensors. First, a direct ignition can occur when an antenna acts as an electrode and generates electrical discharges. Fortunately, this scenario is highly improbable due to the low power of wireless sensors. A second possible scenario is a coupling of RF fields with a large metallic structure. This metallic structure (e.g., a chassis or a net of electrical wires), may act as an antenna by intercepting energy from a surrounding electromagnetic field (wireless sensors) and start resonating at its frequency. The third possible ignition scenario is a coupling of RF signals with parasitic electrical discharges (static electricity, lightning). This effect may lead to an increase of the discharge volume and the energy deposition, which can be the reason for an undesirable ignition1. This study focuses on this scenario. The effect of RF signals at 2.45 GHz on electrical discharges produced by a high-voltage pulse, ranging from 500 ns to $200 mu mathrm{s}$, in a pin-to-pin configuration in air at ambient conditions is investigated. An analysis of the effect of the RF power on the energy deposited by the discharge and the breakdown voltage is performed. The results show that for very short pulses (500 ns), RF signals with a power as large as 50 W do not affect the discharges, while for longer pulses, RF signals start to affect both, the breakdown voltage and the energy deposition.","PeriodicalId":122132,"journal":{"name":"2020 IEEE International Conference on Plasma Science (ICOPS)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121588929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0