P. Bourdon, L. Lombard, A. Durécu, J. Le Gouët, D. Goular, C. Planchat
We describe the coherent combining techniques that can be used to scale up fiber laser power far above single fiber laser limitations, and manipulate their wavefronts. The major configurations and realizations of coherent combining are then presented and compared in terms of maximum achievable number of combined lasers.
{"title":"Coherent combining of fiber lasers","authors":"P. Bourdon, L. Lombard, A. Durécu, J. Le Gouët, D. Goular, C. Planchat","doi":"10.1117/12.2257483","DOIUrl":"https://doi.org/10.1117/12.2257483","url":null,"abstract":"We describe the coherent combining techniques that can be used to scale up fiber laser power far above single fiber laser limitations, and manipulate their wavefronts. The major configurations and realizations of coherent combining are then presented and compared in terms of maximum achievable number of combined lasers.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"193 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116784446","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}
Zhonghui Li, X. Cai, Jingwei Guo, H. Cai, Gao Chen
SRS (Stimulated Raman Scattering) is a very effective method to expand the spectrum range of high power laser, especially in the regime of near IR and middle IR. In this paper SRS of high pressure H2 and D2 with MPC (multiple-pass cell) configuration were reported. Relation of (FS1) first forward Stokes and (BS1) first backward Stokes has been analysis. The process of gain of FS1 was explained. Experimental results also indicated the second Stokes was also generated. D2 SRS of the fundamental output of Nd:YAG laser generates the second Stokes light of 2.92 m. The lasers with wavelength of 2.9 μm have broad applications. Finally, multiple-pass SRS was better for complete conversion of pump laser.
{"title":"Stimulated Raman scattering of high pressure gas in multiple-pass configuration","authors":"Zhonghui Li, X. Cai, Jingwei Guo, H. Cai, Gao Chen","doi":"10.1117/12.2257626","DOIUrl":"https://doi.org/10.1117/12.2257626","url":null,"abstract":"SRS (Stimulated Raman Scattering) is a very effective method to expand the spectrum range of high power laser, especially in the regime of near IR and middle IR. In this paper SRS of high pressure H2 and D2 with MPC (multiple-pass cell) configuration were reported. Relation of (FS1) first forward Stokes and (BS1) first backward Stokes has been analysis. The process of gain of FS1 was explained. Experimental results also indicated the second Stokes was also generated. D2 SRS of the fundamental output of Nd:YAG laser generates the second Stokes light of 2.92 m. The lasers with wavelength of 2.9 μm have broad applications. Finally, multiple-pass SRS was better for complete conversion of pump laser.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"10254 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130011513","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}
V. Losev, S. Alekseev, M. Ivanov, N. Ivanov, G. Mesyats, L. Mikheev, Y. Panchenko, N. Ratakhin, A. Yastremsky
The results of the formation and amplification of positive chirped 0.1 ns laser pulse at a central wavelength of 470 nm in the laser system THL-100 are presented. It is shown that a front-end allows forming a radiation pulse with a Gaussian intensity profile and the energy up to 7 mJ. At amplification in XeF(C-A) amplifier of the pulse with 2-5 mJ energy a saturated mode is realized and 3.2 J output laser beam energy is reached.
{"title":"Amplification of sub-nanosecond pulse in THL-100 laser system","authors":"V. Losev, S. Alekseev, M. Ivanov, N. Ivanov, G. Mesyats, L. Mikheev, Y. Panchenko, N. Ratakhin, A. Yastremsky","doi":"10.1117/12.2256352","DOIUrl":"https://doi.org/10.1117/12.2256352","url":null,"abstract":"The results of the formation and amplification of positive chirped 0.1 ns laser pulse at a central wavelength of 470 nm in the laser system THL-100 are presented. It is shown that a front-end allows forming a radiation pulse with a Gaussian intensity profile and the energy up to 7 mJ. At amplification in XeF(C-A) amplifier of the pulse with 2-5 mJ energy a saturated mode is realized and 3.2 J output laser beam energy is reached.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129903885","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}
Liucheng Li, L. Duo, D. Gong, Yan-hua Ma, Zhiguo Zhang, Yuanhu Wang, Dongjian Zhou, Yuqi Jin
In order to determine the concentrations of trace amount metastable species in chemical lasers, an off-axis cavity enhanced absorption spectrometer for the detection of weak absorption gases has been built with a noise equivalent absorption sensitivity of 1.6x10-8 cm-1. The absorption spectrum of trace amount gaseous ammonia and water vapor was obtained with a spectral resolution of about 78 MHz. A multiple-line absorption spectroscopic method to determine the temperature of gaseous ammonia has been developed by use of multiple lines of ammonia molecule absorption spectrum.
{"title":"Studies of cavity enhanced absorption spectroscopy for weak absorption gas measurements","authors":"Liucheng Li, L. Duo, D. Gong, Yan-hua Ma, Zhiguo Zhang, Yuanhu Wang, Dongjian Zhou, Yuqi Jin","doi":"10.1117/12.2256664","DOIUrl":"https://doi.org/10.1117/12.2256664","url":null,"abstract":"In order to determine the concentrations of trace amount metastable species in chemical lasers, an off-axis cavity enhanced absorption spectrometer for the detection of weak absorption gases has been built with a noise equivalent absorption sensitivity of 1.6x10-8 cm-1. The absorption spectrum of trace amount gaseous ammonia and water vapor was obtained with a spectral resolution of about 78 MHz. A multiple-line absorption spectroscopic method to determine the temperature of gaseous ammonia has been developed by use of multiple lines of ammonia molecule absorption spectrum.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"17 8‐9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120859687","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}
The work presents the experimental investigation of the laser welding of the aluminum-lithium alloys (system Al-Mg-Li) and aluminum alloy (system Al-Cu-Li) doped with Sc. The influence of the nano-structuring of the surface layer welded joint by the cold plastic deformation method on the strength properties of the welded joint is determined. It is founded that, regarding the deformation degree over the thickness, the varying value of the welded joint strength is different for these aluminum alloys.
{"title":"Properties of welded joints in laser welding of aeronautic aluminum-lithium alloys","authors":"A. Malikov, A. Orishich","doi":"10.1117/12.2256016","DOIUrl":"https://doi.org/10.1117/12.2256016","url":null,"abstract":"The work presents the experimental investigation of the laser welding of the aluminum-lithium alloys (system Al-Mg-Li) and aluminum alloy (system Al-Cu-Li) doped with Sc. The influence of the nano-structuring of the surface layer welded joint by the cold plastic deformation method on the strength properties of the welded joint is determined. It is founded that, regarding the deformation degree over the thickness, the varying value of the welded joint strength is different for these aluminum alloys.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121253476","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}
M. Jung, T. Riesbeck, J. Schmitz, T. Baumgärtel, K. Ludewigt, A. Graf
Rheinmetall Waffe Munition has worked since 30 years in the area of High Energy Laser (HEL) for defence applications, starting from pulsed CO2 to pulsed glass rods lasers. In the last decade Rheinmetall Waffe Munition changed to diode pumped solid state laser (DPSSL) technology and has successfully developed, realised and tested a variety of versatile HEL weapon demonstrators for air- and ground defence scenarios like countering rocket, artillery, mortar, missile (RAMM), unmanned aerial systems (UAS) and unexploded ordnances clearing. By employing beam superimposing technology and a modular laser weapon concept, the total optical power has been successively increased. Stationary weapon platforms, military vehicles and naval platforms have been equipped with high energy laser effectors. The contribution gives a summary of the most recent development stages of Rheinmetalls HEL weapon program. In addition to the stationary 30 kW laser weapon demonstrator, we present vehicle based HEL demonstrators: the 5 kW class Mobile HEL Effector Track V, the 20 kW class Mobile HEL Effector Wheel XX and the 50 kW class Mobile HEL Effector Container L and the latest 10 kW HEL effector integrated in the naval weapon platform MLG 27. We describe the capabilities of these demonstrators against different potential targets. Furthermore, we will show the capability of the 30 kW stationary Laser Weapon Demonstrator integrated into an existing ground based air defence system to defeat saturated attacks of RAMM and UAS targets.
{"title":"High energy laser demonstrators for defense applications","authors":"M. Jung, T. Riesbeck, J. Schmitz, T. Baumgärtel, K. Ludewigt, A. Graf","doi":"10.1117/12.2254021","DOIUrl":"https://doi.org/10.1117/12.2254021","url":null,"abstract":"Rheinmetall Waffe Munition has worked since 30 years in the area of High Energy Laser (HEL) for defence applications, starting from pulsed CO2 to pulsed glass rods lasers. In the last decade Rheinmetall Waffe Munition changed to diode pumped solid state laser (DPSSL) technology and has successfully developed, realised and tested a variety of versatile HEL weapon demonstrators for air- and ground defence scenarios like countering rocket, artillery, mortar, missile (RAMM), unmanned aerial systems (UAS) and unexploded ordnances clearing. By employing beam superimposing technology and a modular laser weapon concept, the total optical power has been successively increased. Stationary weapon platforms, military vehicles and naval platforms have been equipped with high energy laser effectors. The contribution gives a summary of the most recent development stages of Rheinmetalls HEL weapon program. In addition to the stationary 30 kW laser weapon demonstrator, we present vehicle based HEL demonstrators: the 5 kW class Mobile HEL Effector Track V, the 20 kW class Mobile HEL Effector Wheel XX and the 50 kW class Mobile HEL Effector Container L and the latest 10 kW HEL effector integrated in the naval weapon platform MLG 27. We describe the capabilities of these demonstrators against different potential targets. Furthermore, we will show the capability of the 30 kW stationary Laser Weapon Demonstrator integrated into an existing ground based air defence system to defeat saturated attacks of RAMM and UAS targets.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127897434","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}
The results of multiterawatt laser beam formation of a visible range in THL-100 hybrid laser system based on titanium-sapphire front-end and photochemical XeF(C-A) boosting amplifier is presented. The front-end delivers up to 20 mJ energy in 50 fs pulses at the second harmonic centered around 475 nm. The active medium of the XeF(C-A) amplifier is produced in a XeF2/N2 mixture irradiated by the VUV radiation from electron beam excited xenon. The laser system is described and the latest results are presented.
{"title":"Formation of the multi-terawatt laser beams in a visible spectrum region","authors":"V. Losev","doi":"10.1117/12.2256225","DOIUrl":"https://doi.org/10.1117/12.2256225","url":null,"abstract":"The results of multiterawatt laser beam formation of a visible range in THL-100 hybrid laser system based on titanium-sapphire front-end and photochemical XeF(C-A) boosting amplifier is presented. The front-end delivers up to 20 mJ energy in 50 fs pulses at the second harmonic centered around 475 nm. The active medium of the XeF(C-A) amplifier is produced in a XeF2/N2 mixture irradiated by the VUV radiation from electron beam excited xenon. The laser system is described and the latest results are presented.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130491096","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}
S. Kubodera, Kazuyuki Fujiyoshi, M. Kaku, M. Katto
We have observed an optical gain at the wavelength of 126 nm in an Ar excimer (Ar2 *) amplifier by utilizing a femtosecond vacuum ultraviolet (VUV) seed beam tuned at 126 nm. The maximum optical gain value of 1.1 cm-1 with a spatial distribution in the optical-field-induced ionization (OFI) Ar plasma was observed. The plasma diagnosis revealed that the plasma contraction near the plasma amplifier axis together with the plasma expansion was a key issue to observe such a high optical gain value inside the Ar plasma filament. The center axis of the contracted plasma amplifier showed the high electron density more than 1018 cm-3 even after 100 ns from the plasma production of Ar at 1 MPa. Our OFI plasma/excimer kinetics code reproduced the temporal progress of the optical gain distribution as well as the maximum gain value.
{"title":"Amplification of femtosecond pulses at 126 nm in optical field-induced plasma filamentation in Ar","authors":"S. Kubodera, Kazuyuki Fujiyoshi, M. Kaku, M. Katto","doi":"10.1117/12.2256014","DOIUrl":"https://doi.org/10.1117/12.2256014","url":null,"abstract":"We have observed an optical gain at the wavelength of 126 nm in an Ar excimer (Ar2 *) amplifier by utilizing a femtosecond vacuum ultraviolet (VUV) seed beam tuned at 126 nm. The maximum optical gain value of 1.1 cm-1 with a spatial distribution in the optical-field-induced ionization (OFI) Ar plasma was observed. The plasma diagnosis revealed that the plasma contraction near the plasma amplifier axis together with the plasma expansion was a key issue to observe such a high optical gain value inside the Ar plasma filament. The center axis of the contracted plasma amplifier showed the high electron density more than 1018 cm-3 even after 100 ns from the plasma production of Ar at 1 MPa. Our OFI plasma/excimer kinetics code reproduced the temporal progress of the optical gain distribution as well as the maximum gain value.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134569008","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}
J. Grosek, S. Naderi, Benjamin Q. Oliker, R. A. Lane, I. Dajani, T. Madden
The physics of high brightness, high-power lasers present a variety of challenges with respect to simulation. The Air Force Research Laboratory is developing high-fidelity models for Yb-doped, Tm-doped, and Raman fiber amplifiers, hollow-core optical fiber gas lasers, and diode pumped alkali lasers. The approach to simulation and the physics specific to each laser technology are described, along with highlights of results, and relevant modeling considerations and limitations.
{"title":"Laser simulation at the Air Force Research Laboratory","authors":"J. Grosek, S. Naderi, Benjamin Q. Oliker, R. A. Lane, I. Dajani, T. Madden","doi":"10.1117/12.2265048","DOIUrl":"https://doi.org/10.1117/12.2265048","url":null,"abstract":"The physics of high brightness, high-power lasers present a variety of challenges with respect to simulation. The Air Force Research Laboratory is developing high-fidelity models for Yb-doped, Tm-doped, and Raman fiber amplifiers, hollow-core optical fiber gas lasers, and diode pumped alkali lasers. The approach to simulation and the physics specific to each laser technology are described, along with highlights of results, and relevant modeling considerations and limitations.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124007727","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}
The hollow beam has a variety of special physical properties and can be applied to the optical catheter, optical trap, generation of the light trap and many other important fields. In this paper the light-field conversion of the Gaussian beam passing through double axicons and generating the hollow beam is theoretical derived and simulated using the light-field propagation method. The influence of several parameters on the near and far field intensity distribution of the hollow beam is discussed. We find that the hollow beam with different light-field can be generated by controlling these parameters and this has a great potential in terms of micro manipulation, optical trap and other fields.
{"title":"Investigation of hollow beam generated by double axicons and its propagation properties","authors":"Peng Wang, Xiao Li, Yaping Shang, Xiaojun Xu","doi":"10.1117/12.2256489","DOIUrl":"https://doi.org/10.1117/12.2256489","url":null,"abstract":"The hollow beam has a variety of special physical properties and can be applied to the optical catheter, optical trap, generation of the light trap and many other important fields. In this paper the light-field conversion of the Gaussian beam passing through double axicons and generating the hollow beam is theoretical derived and simulated using the light-field propagation method. The influence of several parameters on the near and far field intensity distribution of the hollow beam is discussed. We find that the hollow beam with different light-field can be generated by controlling these parameters and this has a great potential in terms of micro manipulation, optical trap and other fields.","PeriodicalId":293926,"journal":{"name":"International Symposium on High Power Laser Systems and Applications","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121055615","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}