1
|
Qi P, Qian W, Guo L, Xue J, Zhang N, Wang Y, Zhang Z, Zhang Z, Lin L, Sun C, Zhu L, Liu W. Sensing with Femtosecond Laser Filamentation. SENSORS (BASEL, SWITZERLAND) 2022; 22:7076. [PMID: 36146424 PMCID: PMC9504994 DOI: 10.3390/s22187076] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 05/25/2023]
Abstract
Femtosecond laser filamentation is a unique nonlinear optical phenomenon when high-power ultrafast laser propagation in all transparent optical media. During filamentation in the atmosphere, the ultrastrong field of 1013-1014 W/cm2 with a large distance ranging from meter to kilometers can effectively ionize, break, and excite the molecules and fragments, resulting in characteristic fingerprint emissions, which provide a great opportunity for investigating strong-field molecules interaction in complicated environments, especially remote sensing. Additionally, the ultrastrong intensity inside the filament can damage almost all the detectors and ignite various intricate higher order nonlinear optical effects. These extreme physical conditions and complicated phenomena make the sensing and controlling of filamentation challenging. This paper mainly focuses on recent research advances in sensing with femtosecond laser filamentation, including fundamental physics, sensing and manipulating methods, typical filament-based sensing techniques and application scenarios, opportunities, and challenges toward the filament-based remote sensing under different complicated conditions.
Collapse
Affiliation(s)
- Pengfei Qi
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Wenqi Qian
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Lanjun Guo
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Jiayun Xue
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Nan Zhang
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Yuezheng Wang
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Zhi Zhang
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Tianjin 300350, China
| | - Zeliang Zhang
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
| | - Lie Lin
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Tianjin 300350, China
| | - Changlin Sun
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Tianjin 300350, China
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Liguo Zhu
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Weiwei Liu
- Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Tianjin 300350, China
| |
Collapse
|
2
|
Wang XK, Ye JS, Sun WF, Han P, Hou L, Zhang Y. Terahertz near-field microscopy based on an air-plasma dynamic aperture. LIGHT, SCIENCE & APPLICATIONS 2022; 11:129. [PMID: 35525862 PMCID: PMC9079089 DOI: 10.1038/s41377-022-00822-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/13/2022] [Accepted: 04/27/2022] [Indexed: 06/14/2023]
Abstract
Terahertz (THz) near-field microscopy retains the advantages of THz radiation and realizes sub-wavelength imaging, which enables applications in fundamental research and industrial fields. In most THz near-field microscopies, the sample surface must be approached by a THz detector or source, which restricts the sample choice. Here, a technique was developed based on an air-plasma dynamic aperture, where two mutually perpendicular air-plasmas overlapped to form a cross-filament above a sample surface that modulated an incident THz beam. THz imaging with quasi sub-wavelength resolution (approximately λ/2, where λ is the wavelength of the THz beam) was thus observed without approaching the sample with any devices. Damage to the sample by the air-plasmas was avoided. Near-field imaging of four different materials was achieved, including metallic, semiconductor, plastic, and greasy samples. The resolution characteristics of the near-field system were investigated with experiment and theory. The advantages of the technique are expected to accelerate the advancement of THz microscopy.
Collapse
Affiliation(s)
- Xin-Ke Wang
- Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China
| | - Jia-Sheng Ye
- Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China
| | - Wen-Feng Sun
- Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China
| | - Peng Han
- Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China
| | - Lei Hou
- Applied Physics Department, Xian University of Technology, Xian, Shaanxi, 710048, China
| | - Yan Zhang
- Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics Ministry of Education, Department of Physics, Capital Normal University, Beijing, 100048, China.
| |
Collapse
|
3
|
Zhang L, Liu J, Gong W, Jiang H, Liu S. Diffraction based single pulse measurement of air ionization dynamics induced by femtosecond laser. OPTICS EXPRESS 2021; 29:18601-18610. [PMID: 34154113 DOI: 10.1364/oe.427364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
A single pulse diffraction method to probe the plasma column evolution of the air ionization induced by the femtosecond laser pulse has been proposed. By utilizing a linearly chirped pulse as the probe light, the spatiotemporal evolution spectrum of the plasma column can be acquired in a single measurement. A method based on the Fresnel diffraction integral is proposed to extract the evolution of the phase shift after the probe light is crossing through the plasma column. Results show that the plasma expands rapidly within 7 ps due to the ionization, and then reaches a steady state with a diameter of about 80 μm with the pump pulse energy of 1 mJ. Furtherly, the temporal profile of the free electron density and the refractive index in the plasma region were determined using the corresponding physical models. The single-shot method can be expected to broaden the way for detecting the dynamics of the femtosecond laser-induced plasma.
Collapse
|
4
|
Ju J, Sun H, Hu X, Liu Y, Liu Y, Wang J, Wang C, Wang TJ, Guo X, Liu J, Chin SL, Li R, Xu Z. Temporal evolution of condensation and precipitation induced by a 22-TW laser. OPTICS EXPRESS 2018; 26:2785-2793. [PMID: 29401814 DOI: 10.1364/oe.26.002785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 01/21/2018] [Indexed: 06/07/2023]
Abstract
Water condensation and precipitation induced by 22-TW 800-nm laser pulses at 1 Hz in an open cloud chamber were investigated in a time-resolved manner. Two parts of precipitation in two independent periods of time were observed directly following each laser shot. One part started around the filament zone at t < 500 μs and ended at t ≅ 1.5 ms after the arrival of the femtosecond laser pulse. The other following the laser-induced energetic air motion (turbulence), started at t ≅ 20 ms and ended at t ≅ 120 ms. Meanwhile, the phase transitions of large-size condensation droplets with diameters of 400-500 μm from liquid to solid (ice) in a cold area (T < -30 °C) were captured at t ≅ 20 ms.
Collapse
|
5
|
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.
Collapse
|
6
|
Aleksandrov NL, Bodrov SB, Tsarev MV, Murzanev AA, Sergeev YA, Malkov YA, Stepanov AN. Decay of femtosecond laser-induced plasma filaments in air, nitrogen, and argon for atmospheric and subatmospheric pressures. Phys Rev E 2016; 94:013204. [PMID: 27575227 DOI: 10.1103/physreve.94.013204] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Indexed: 11/07/2022]
Abstract
The temporal evolution of a plasma channel at the trail of a self-guided femtosecond laser pulse was studied experimentally and theoretically in air, nitrogen (with an admixture of ∼3% O_{2}), and argon in a wide range of gas pressures (from 2 to 760 Torr). Measurements by means of transverse optical interferometry and pulsed terahertz scattering techniques showed that plasma density in air and nitrogen at atmospheric pressure reduces by an order of magnitude within 3-4 ns and that the decay rate decreases with decreasing pressure. The argon plasma did not decay within several nanoseconds for pressures of 50-760 Torr. We extended our theoretical model previously applied for atmospheric pressure air plasma to explain the plasma decay in the gases under study and to show that allowance for plasma channel expansion affects plasma decay at low pressures.
Collapse
Affiliation(s)
- N L Aleksandrov
- Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia
| | - S B Bodrov
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.,University of Nizhny Novgorod, Nizhny Novgorod 603950, Russia
| | - M V Tsarev
- University of Nizhny Novgorod, Nizhny Novgorod 603950, Russia
| | - A A Murzanev
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
| | - Yu A Sergeev
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
| | - Yu A Malkov
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
| | - A N Stepanov
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
| |
Collapse
|
7
|
Ju J, Sun H, Sridharan A, Wang TJ, Wang C, Liu J, Li R, Xu Z, Chin SL. Laser-filament-induced snow formation in a subsaturated zone in a cloud chamber: experimental and theoretical study. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:062803. [PMID: 24483507 DOI: 10.1103/physreve.88.062803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Indexed: 06/03/2023]
Abstract
1 kHz, 2 mJ, 45 fs, 800 nm laser pulses were fired into a laboratory diffusion cloud chamber through a subsaturated zone (relative humidity ∼73%, T ∼ 4.3 °C). After 60 min of laser irradiation, an oval-shaped snow pile was observed right below the filament center and weighed ∼12.0 mg. The air current velocity at the edge of the vortices was estimated to be ∼16.5 cm/s. Scattering scenes recorded from the side show that filament-induced turbulence were formed inside the cloud chamber with two vortices below the filament. Two-dimensional simulations of the air flow motion in two cross sections of the cloud chamber confirm that the turbulent vortices exist below the filament. Based upon this simulation, we deduce that the vortices indeed have a three-dimensional elliptical shape. Hence, we propose that inside vortices where the humidity was supersaturated or saturated the condensation nuclei, namely, HNO(3), N(2)(+), O(2)(+) and other aerosols and impurities, were activated and grew in size. Large-sized particles would eventually be spun out along the fast moving direction towards the cold plate and formed an oval-shaped snow pile at the end.
Collapse
Affiliation(s)
- Jingjing Ju
- Department of Physics, Engineering Physics and Optics and Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, QC G1V 0A6, Canada and State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Haiyi Sun
- State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Aravindan Sridharan
- Department of Physics, Engineering Physics and Optics and Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, QC G1V 0A6, Canada
| | - Tie-Jun Wang
- Department of Physics, Engineering Physics and Optics and Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, QC G1V 0A6, Canada and State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Cheng Wang
- State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Jiansheng Liu
- State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Ruxin Li
- State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - Zhizhan Xu
- State Key Lab of High Laser Field Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, No. 390, Qinghe Road, Jiading District, Shanghai 201800, China
| | - See Leang Chin
- Department of Physics, Engineering Physics and Optics and Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, QC G1V 0A6, Canada
| |
Collapse
|
8
|
Yang H, Liu P, Lu H, Ge X, Li R, Xu Z. Time-evolution of electron density in plasma measured by high-order harmonic generation. OPTICS EXPRESS 2012; 20:19449-19454. [PMID: 23038587 DOI: 10.1364/oe.20.019449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We propose a new method of measuring the electron density in plasma by high-order harmonic generation (HHG) of intense two-color femtosecond (fs) laser. As the 800 nm fundamental beam is introduced after its second harmonic generation (SHG) beam, the recovery of HHG by the fundamental pulses at a delay of ~40 ps indicates the decay time of the generated plasma. The electron-ion recombination rate and electron density decay are revealed by fitting the harmonic emission to the model that accounts for depletion of neutral atoms, phase mismatch and re-absorption of HHG.
Collapse
Affiliation(s)
- Hua Yang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
| | | | | | | | | | | |
Collapse
|
9
|
Ju J, Liu J, Wang C, Sun H, Wang W, Ge X, Li C, Chin SL, Li R, Xu Z. Laser-filamentation-induced condensation and snow formation in a cloud chamber. OPTICS LETTERS 2012; 37:1214-1216. [PMID: 22466199 DOI: 10.1364/ol.37.001214] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Using 1 kHz, 9 mJ femtosecond laser pulses, we demonstrate laser-filamentation-induced spectacular snow formation in a cloud chamber. An intense updraft of warm moist air is generated owing to the continuous heating by the high-repetition filamentation. As it encounters the cold air above, water condensation and large-sized particles spread unevenly across the whole cloud chamber via convection and cyclone like action on a macroscopic scale. This indicates that high-repetition filamentation plays a significant role in macroscopic laser-induced water condensation and snow formation.
Collapse
Affiliation(s)
- Jingjing Ju
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Zhang N, Wu Z, Xu K, Zhu X. Characteristics of micro air plasma produced by double femtosecond laser pulses. OPTICS EXPRESS 2012; 20:2528-2538. [PMID: 22330490 DOI: 10.1364/oe.20.002528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dynamic characteristics of air plasma generated by focused double collinear femtosecond laser pulses with a time interval of 10 ns are experimentally investigated. The air plasma emission changes significantly when altering the energy ratio between the two laser pulses. Time-resolved shadowgraphic measurements reveal that a small volume of transient vacuum is formed inside the air shock wave produced by the first laser pulse, which causes the second laser pulse induced ionization zone to present as two separate sections in space. Also recorded is strong scattering of the second laser pulse by the ionized air just behind the ionization front of the first laser pulse produced shock wave. Due to the high intensity of the scattered light, coherent Thomson scattering enhanced by plasma instabilities is believed to be the main scattering mechanism in this case.
Collapse
Affiliation(s)
- Nan Zhang
- Institute of Modern Optics, Nankai University, Key Laboratory of Optical Information Science and Technology, Ministry of Education, Tianjin 300071, China
| | | | | | | |
Collapse
|
11
|
Sun Z, Chen J, Rudolph W. Determination of the transient electron temperature in a femtosecond-laser-induced air plasma filament. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:046408. [PMID: 21599317 DOI: 10.1103/physreve.83.046408] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Indexed: 05/30/2023]
Abstract
The transient electron temperature in a weakly ionized femtosecond-laser-produced air plasma filament was determined from optical absorption and diffraction experiments. The electron temperature and plasma density decay on similar time scales of a few hundred picoseconds. Comparison with plasma theory reveals the importance of inelastic collisions that lead to energy transfer to vibrational degrees of freedom of air molecules during the plasma cooling.
Collapse
Affiliation(s)
- Zhanliang Sun
- University of New Mexico, Department of Physics and Astronomy, Albuquerque, New Mexico 87131, USA.
| | | | | |
Collapse
|
12
|
Bodrov S, Bukin V, Tsarev M, Murzanev A, Garnov S, Aleksandrov N, Stepanov A. Plasma filament investigation by transverse optical interferometry and terahertz scattering. OPTICS EXPRESS 2011; 19:6829-6835. [PMID: 21451710 DOI: 10.1364/oe.19.006829] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Transverse plasma distribution with 10(17) cm(-3) maximum electron density and 150 μm transverse size in a plasma filament formed in air by an intense femtosecond laser pulse was measured by means of optical interferometry. Two orders of magnitude decay of the electron density within 2 ns was obtained by combined use of the interferometry and newly proposed terahertz scattering techniques. Excellent agreement was obtained between the measured plasma density evolution and theoretical calculation.
Collapse
Affiliation(s)
- Sergey Bodrov
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia.
| | | | | | | | | | | | | |
Collapse
|
13
|
Liu XL, Lu X, Liu X, Xi TT, Liu F, Ma JL, Zhang J. Tightly focused femtosecond laser pulse in air: from filamentation to breakdown. OPTICS EXPRESS 2010; 18:26007-17. [PMID: 21164948 DOI: 10.1364/oe.18.026007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The propagation of tightly focused femtosecond laser pulse with numerical aperture of 0.12 in air is investigated experimentally. The formation and evolution of the filament bunch are recorded by time-resolved shadowgraph with laser energy from 2.4 mJ to 47 mJ. The distribution of electron density in breakdown area is retrieved using Nomarski interferometer. It is found that intensity clamping during filamentation effect still play a role even under strong external focusing. The electron density in some interaction zones is higher than 3 × 10(19) cm(-3), which indicates that each air molecule there is ionized.
Collapse
Affiliation(s)
- Xiao-Long Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | | | | | | | | | | | | |
Collapse
|
14
|
Théberge F, Liu W, Simard PT, Becker A, Chin SL. Plasma density inside a femtosecond laser filament in air: strong dependence on external focusing. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 74:036406. [PMID: 17025753 DOI: 10.1103/physreve.74.036406] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2006] [Indexed: 05/12/2023]
Abstract
Our experiment shows that external focusing strongly influences the plasma density and the diameter of femtosecond Ti-sapphire laser filaments generated in air. The control of plasma filament parameters is suitable for many applications such as remote spectroscopy, laser induced electrical discharge, and femtosecond laser material interactions. The measurements of the filament showed the plasma density increases from 10(15)cm(-3) to 2 x 10(18)cm(-3) when the focal length decreases from 380 cm to 10 cm while the diameter of the plasma column varies from 30 microm to 90 microm. The experimental results are in good qualitative agreement with the results of numerical simulations.
Collapse
Affiliation(s)
- Francis Théberge
- Centre d'Optique, Photonique et Laser and Département de Physique, de Génie Physique et d'Optique, Université Laval, Québec, Canada, G1K 7P4
| | | | | | | | | |
Collapse
|
15
|
Deng YP, Zhu JB, Ji ZG, Liu JS, Shuai B, Li RX, Xu ZZ, Théberge F, Chin SL. Transverse evolution of a plasma channel in air induced by a femtosecond laser. OPTICS LETTERS 2006; 31:546-8. [PMID: 16496915 DOI: 10.1364/ol.31.000546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We investigate the evolution of filamentation in air by using a longitudinal diffraction method and a plasma fluorescence imaging technique. The diameter of a single filament in which the intensity is clamped increases as the energy of the pump light pulse increases, until multiple filaments appear.
Collapse
Affiliation(s)
- Y P Deng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
| | | | | | | | | | | | | | | | | |
Collapse
|