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Liu Y, Yin F, Wang TJ, Leng Y, Li R, Xu Z, Chin SL. Stable, intense supercontinuum light generation at 1 kHz by electric field assisted femtosecond laser filamentation in air. LIGHT, SCIENCE & APPLICATIONS 2024; 13:42. [PMID: 38307847 PMCID: PMC10837124 DOI: 10.1038/s41377-023-01364-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 12/04/2023] [Accepted: 12/19/2023] [Indexed: 02/04/2024]
Abstract
Supercontinuum (SC) light source has advanced ultrafast laser spectroscopy in condensed matter science, biology, physics, and chemistry. Compared to the frequently used photonic crystal fibers and bulk materials, femtosecond laser filamentation in gases is damage-immune for supercontinuum generation. A bottleneck problem is the strong jitters from filament induced self-heating at kHz repetition rate level. We demonstrated stable kHz supercontinuum generation directly in air with multiple mJ level pulse energy. This was achieved by applying an external DC electric field to the air plasma filament. Beam pointing jitters of the 1 kHz air filament induced SC light were reduced by more than 2 fold. The stabilized high repetition rate laser filament offers the opportunity for stable intense SC generation and its applications in air.
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Affiliation(s)
- Yaoxiang Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Fukang Yin
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - Tie-Jun Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China.
| | - Yuxin Leng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China.
| | - Ruxin Li
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China.
| | - Zhizhan Xu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China
| | - See Leang Chin
- Centre d'Optique, Photonique et Laser (COPL) and Département de physique, de génie physique et d'optique, Université Laval, Québec, Québec, Canada
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Kou R, Zhong Y, Qiao Y. Flow Electrification of a Corona-Charged Polyethylene Terephthalate Film. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9571-9577. [PMID: 32702991 DOI: 10.1021/acs.langmuir.0c01596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Corona charging of a free-standing polymer film can produce a quasi-permanent potential difference across the film thickness, while the absolute amplitude of the surface voltage may be highly sensitive to the free charges. To precisely control the voltage distribution, we investigated the flow electrification technology by exposing corona-charged polyethylene terephthalate films to sodium salt solutions. The surface voltage and the free-charge density were adjusted by the salt concentration, the anion size, and the flow rate. The dipolar component of electric potential remained unchanged. This result has significant scientific interest and technological importance to surface treatment, filtration, energy harvesting, among others.
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Affiliation(s)
- Rui Kou
- Department of Structural Engineering, University of California-San Diego, La Jolla, California 92093-0085, United States
| | - Ying Zhong
- Department of Structural Engineering, University of California-San Diego, La Jolla, California 92093-0085, United States
- Department of Mechanical Engineering, University of South Florida, Tampa, Florida 33620, United States
| | - Yu Qiao
- Department of Structural Engineering, University of California-San Diego, La Jolla, California 92093-0085, United States
- Program of Materials Science and Engineering, University of California-San Diego, La Jolla, California 92093, United States
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A Review of Femtosecond Laser-Induced Emission Techniques for Combustion and Flow Field Diagnostics. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9091906] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The applications of femtosecond lasers to the diagnostics of combustion and flow field have recently attracted increasing interest. Many novel spectroscopic methods have been developed in obtaining non-intrusive measurements of temperature, velocity, and species concentrations with unprecedented possibilities. In this paper, several applications of femtosecond-laser-based incoherent techniques in the field of combustion diagnostics were reviewed, including two-photon femtosecond laser-induced fluorescence (fs-TPLIF), femtosecond laser-induced breakdown spectroscopy (fs-LIBS), filament-induced nonlinear spectroscopy (FINS), femtosecond laser-induced plasma spectroscopy (FLIPS), femtosecond laser electronic excitation tagging velocimetry (FLEET), femtosecond laser-induced cyano chemiluminescence (FLICC), and filamentary anemometry using femtosecond laser-extended electric discharge (FALED). Furthermore, prospects of the femtosecond-laser-based combustion diagnostic techniques in the future were analyzed and discussed to provide a reference for the relevant researchers.
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Du S, Wang TJ, Zhu Z, Liu Y, Chen N, Zhang J, Guo H, Sun H, Ju J, Wang C, Liu J, Chin SL, Li R, Xu Z. Laser guided ionic wind. Sci Rep 2018; 8:13511. [PMID: 30202066 PMCID: PMC6131152 DOI: 10.1038/s41598-018-31993-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 08/17/2018] [Indexed: 11/12/2022] Open
Abstract
We report on a method to experimentally generate ionic wind by coupling an external large electric field with an intense femtosecond laser induced air plasma channel. The measured ionic wind velocity could be as strong as >4 m/s. It could be optimized by increasing the strength of the applied electric field and the volume of the laser induced plasma channel. The experimental observation was qualitatively confirmed by a numerical simulation of spatial distribution of the electric field. The ionic wind can be generated outside a high-voltage geometry, even at remote distances.
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Affiliation(s)
- Shengzhe Du
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Tie-Jun Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
| | - Zhongbin Zhu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Yaoxiang Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Na Chen
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Jianhao Zhang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Hao Guo
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Haiyi Sun
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Jingjing Ju
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Cheng Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Jiansheng Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
| | - See Leang Chin
- Centre d'Optique, Photonique et Laser (COPL) and Département de physique, de génie physique et d'optique, Université Laval, Québec, Québec, G1V 0A6, Canada
| | - Ruxin Li
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | - Zhizhan Xu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
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Li B, Tian Y, Gao Q, Zhang D, Li X, Zhu Z, Li Z. Filamentary anemometry using femtosecond laser-extended electric discharge - FALED. OPTICS EXPRESS 2018; 26:21132-21140. [PMID: 30119417 DOI: 10.1364/oe.26.021132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
We demonstrate a non-contact spatiotemporally resolved comprehensive method for gas flow velocity field measurement: Filamentary Anemometry using femtosecond Laser-extended Electric Discharge (FALED). A faint thin plasma channel was generated in ambient air by focusing an 800-nm laser beam of 45 fs, which was used to ignite a pulsed electric discharge between two electrodes separated over 10 mm. The power supplier provided a maximum voltage up to 5 kV and was operated at a burst mode with a current duration of less than 20 ns and a pulse-to-pulse separation of 40 μs. The laser-guided thin filamentary discharge plasma column was blowing up perpendicularly by an air jet placed beneath in-between the two electrodes. Although the discharge pulse was short, the conductivity of the plasma channel was observed to sustain much longer, so that a sequence of discharge filaments was generated as the plasma channel being blown up by the jet flow. The sequential bright thin discharge filaments can be photographed using a household camera to calculate the flow velocity distribution of the jet flow. For a direct comparison, a flow field measurement using FLEET [Appl. Opt. 50, 5158 (2011)] was also performed. The results indicate that the FALED technique can provide instantaneous nonintrusive flow field velocity measurement with good accuracy.
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Highly extended filaments in aqueous gold nano-particle colloidals. Sci Rep 2018; 8:5957. [PMID: 29654307 PMCID: PMC5899100 DOI: 10.1038/s41598-018-24479-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 04/03/2018] [Indexed: 11/22/2022] Open
Abstract
A new regime of filamentation has been discovered in aqueous gold nanoparticle colloidals (AGNC). Different from filamentation in liquids, in this regime, by doping water with gold nanoparticles, there is no observable multiple small-scale filaments, but instead a spatially continuous plasma channel is formed. The length of the filament is more than ten times as compared with that in water. Filamentation in AGNC is characterized by a colorful light channel, with generated supercontinuum ranging from 400 nm to 650 nm which is scattered along a cyan-orange path.
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Wolf JP. Short-pulse lasers for weather control. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:026001. [PMID: 28783040 DOI: 10.1088/1361-6633/aa8488] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Filamentation of ultra-short TW-class lasers recently opened new perspectives in atmospheric research. Laser filaments are self-sustained light structures of 0.1-1 mm in diameter, spanning over hundreds of meters in length, and producing a low density plasma (1015-1017 cm-3) along their path. They stem from the dynamic balance between Kerr self-focusing and defocusing by the self-generated plasma and/or non-linear polarization saturation. While non-linearly propagating in air, these filamentary structures produce a coherent supercontinuum (from 230 nm to 4 µm, for a 800 nm laser wavelength) by self-phase modulation (SPM), which can be used for remote 3D-monitoring of atmospheric components by Lidar (Light Detection and Ranging). However, due to their high intensity (1013-1014 W cm-2), they also modify the chemical composition of the air via photo-ionization and photo-dissociation of the molecules and aerosols present in the laser path. These unique properties were recently exploited for investigating the capability of modulating some key atmospheric processes, like lightning from thunderclouds, water vapor condensation, fog formation and dissipation, and light scattering (albedo) from high altitude clouds for radiative forcing management. Here we review recent spectacular advances in this context, achieved both in the laboratory and in the field, reveal their underlying mechanisms, and discuss the applicability of using these new non-linear photonic catalysts for real scale weather control.
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Affiliation(s)
- J P Wolf
- Department of Applied Physics (GAP), University of Geneva, 1211 Geneva 4, Switzerland
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Long-lived laser-induced arc discharges for energy channeling applications. Sci Rep 2017; 7:13801. [PMID: 29062077 PMCID: PMC5653766 DOI: 10.1038/s41598-017-14054-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 10/06/2017] [Indexed: 11/08/2022] Open
Abstract
Laser filamentation offers a promising way for the remote handling of large electrical power in the form of guided arc discharges. We here report that it is possible to increase by several orders of magnitude the lifetime of straight plasma channels from filamentation-guided sparks in atmospheric air. A 30 ms lifetime can be reached using a low-intensity, 100 mA current pulse. Stability of the plasma shape is maintained over such a timescale through a continuous Joule heating from the current. This paves the way for applications based on the generation of straight, long duration plasma channels, like virtual plasma antennas or contactless transfer of electric energy.
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Ju J, Wang TJ, Li R, Du S, Sun H, Liu Y, Tian Y, Bai Y, Liu Y, Chen N, Wang J, Wang C, Liu J, Chin SL, Xu Z. Corona discharge induced snow formation in a cloud chamber. Sci Rep 2017; 7:11749. [PMID: 28924141 PMCID: PMC5603531 DOI: 10.1038/s41598-017-12002-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 09/01/2017] [Indexed: 11/09/2022] Open
Abstract
Artificial rainmaking is in strong demand especially in arid regions. Traditional methods of seeding various Cloud Condensation Nuclei (CCN) into the clouds are costly and not environment friendly. Possible solutions based on ionization were proposed more than 100 years ago but there is still a lack of convincing verification or evidence. In this report, we demonstrated for the first time the condensation and precipitation (or snowfall) induced by a corona discharge inside a cloud chamber. Ionic wind was found to have played a more significant role than ions as extra CCN. In comparison with another newly emerging femtosecond laser filamentation ionization method, the snow precipitation induced by the corona discharge has about 4 orders of magnitude higher wall-plug efficiency under similar conditions.
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Affiliation(s)
- Jingjing Ju
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Tie-Jun Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Ruxin Li
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China.
| | - Shengzhe Du
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Haiyi Sun
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Yonghong Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China.,MOE Key Laboratory of Advanced Micro-structured Material, Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Ye Tian
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Yafeng Bai
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Yaoxiang Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Na Chen
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Jingwei Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Cheng Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China
| | - Jiansheng Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China.,IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - S L Chin
- Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, QC G1V 0A6, Canada
| | - Zhizhan Xu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and fine Mechanics (SIOM), Chinese Academy of Sciences, No. 390, Qinghe Road, Jiading District, Shanghai, 201800, China.
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Liu Y, Wang T, Chen N, Du S, Ju J, Sun H, Wang C, Liu J, Lu H, Chin SL, Li R, Xu Z, Wang Z. Probing the effective length of plasma inside a filament. OPTICS EXPRESS 2017; 25:11078-11087. [PMID: 28788791 DOI: 10.1364/oe.25.011078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present a novel method based on plasma-guided corona discharges to probe the plasma density longitudinal distribution, which is particularly good for the weakly ionized plasmas (~1014 cm-3). With this method, plasma density longitudinal distribution inside both a weakly ionized plasma and a filament were characterized. When a high voltage electric field was applied onto a plasma channel, the original ionization created by a laser pulse would be enhanced and streamer coronas formed along the channel. By measuring the fluorescence of enhanced ionization, in particular, on both ends of a filament, the weak otherwise invisible plasma regions created by the laser pulse were identified. The observed plasma guided coronas were qualitatively understood by solving a 3D Maxwell equation through finite element analysis. The technique paves a new way to probe low density plasma and to precisely measure the effective length of plasma inside a filament.
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Théberge F, Daigle JF, Kieffer JC, Vidal F, Châteauneuf M. Laser-guided energetic discharges over large air gaps by electric-field enhanced plasma filaments. Sci Rep 2017; 7:40063. [PMID: 28053312 PMCID: PMC5214843 DOI: 10.1038/srep40063] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/30/2016] [Indexed: 11/16/2022] Open
Abstract
Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electric pulse from a Tesla coil allowed to stimulate and maintain the highly conductive channel during few milliseconds in order to guide a subsequent 500 times more energetic discharge from a 30-kV DC source. This DC discharge was laser-guided over an air gap length of two metres, which is more than two orders of magnitude longer than the expected natural discharge length. Long plasma channel induced by laser pulses and stimulated by an external high-voltage source opens the way for wireless and efficient transportation of energetic current pulses over long air gaps and potentially for guiding lightning.
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Houard A, Jukna V, Point G, André YB, Klingebiel S, Schultze M, Michel K, Metzger T, Mysyrowicz A. Study of filamentation with a high power high repetition rate ps laser at 1.03 µm. OPTICS EXPRESS 2016; 24:7437-7448. [PMID: 27137034 DOI: 10.1364/oe.24.007437] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We study the propagation of intense, high repetition rate laser pulses of picosecond duration at 1.03 µm central wavelength through air. Evidence of filamentation is obtained from measurements of the beam profile as a function of distance, from photoemission imaging and from spatially resolved sonometric recordings. Good agreement is found with numerical simulations. Simulations reveal an important self shortening of the pulse duration, suggesting that laser pulses with few optical cycles could be obtained via double filamentation. An important lowering of the voltage required to induce guided electric discharges between charged electrodes is measured at high laser pulse repetition rate.
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