Physics and applications of atmospheric nonlinear optics and filamentation

Abstract

Abstract:We review the properties and applications of ultrashort laser pulses in the atmosphere, with a particular focus on filamentation. Filamentation is a non-linear propagation regime specific of ultrashort and ultraintense laser pulses in the atmosphere. Typical applications include remote sensing of atmospheric gases and aerosols, lightning control, laserinduced spectroscopy, coherent anti-stokes Raman scattering, and the generation of sub-THz radiation. References and Links 1. P. L. Kelley, "Self-focusing of optical beams," Phys. Rev. Lett. 15, 1005-1008 (1965); Erratum in Phys.Rev. Lett. 16, 384 (1965) 2. G. A. Askar'yan, "The self-focusing effect," Sov. Phys. J. 16 680 (1974) 3. A. Braun, G. Korn, X. Liu, D. Du, J. Squier, G. Mourou, "Self-channeling of high-peak-power femtosecond laser pulses in air," Opt. Lett. 20, 73-75 (1995) 4. L. Roso-Franco, "Self-reflected wave insid a very dense saturable absorber," Phys. Rev. Lett. 55, 2149-2151 (1985) 5. R. R. Alfano, S. L. Shapiro, "Emission in the region 4000 to 7000 Å," Phys. Rev. Lett. 24, 584-587 (1970) 6. R. R. Alfano, S. L. Shapiro, "Observation of self-phase modulation and small-scale filaments in crystals and glasses," Phys. Rev. Lett. 24, 592-595 (1970) 7.R. R. Alfano, S. L. Shapiro, "Direct distortion of electric clouds of rare-gas atoms in intense electric fields," Phys. Rev. Lett. 24, 1217Lett. 24, -1220Lett. 24, (1970. A. Brodeur, S. L. Chin, "Ultrafast white-light continuum generation and self-focusing in transparent condensed media," J. Opt. Soc. Am. B 16, 637-650 (1999) 9. Y. Shen, "The principles of nonlinear optics," John Wiley & Sons (1984) 10. G. Yang, Y. Shen, "Spectral broadening of ultrashort pulses in a nonlinear medium," Opt. Lett. 9, 510-512 (1984) 11. A. L. Gaeta, "Catastrophic collapse of ultrashort pulses, Phys. Rev. Lett." 84, 3582-3585 (2000) 12. K. Ranka, R. W. Schirmer, A. L. Gaeta, "Observation of pulse splitting in nonlinear dispersive media," Phys. Rev. Lett. 77, 3783-3786 (1996) 13. A. Proulx, A. Talebpour, S. Petit, S. L. Chin, "Fast pulsed electric field created from the self-generated filament of a femtosecond Ti:Sapphire laser pulse in air," Opt. Commun. 174, 305-309 (2000) 14. S. Tzortzakis, M. A. Franco, Y.-B. André, A. Chiron, B. Lamouroux, B. S. Prade, A. Mysyrowicz, "Formation of a conducting channel in air by self-guided femtosecond laser pulses," Phys. Rev. E 60, R3505-R3507 (1999) 15. S. Tzortzakis, B. Prade, M. Franco, A. Mysyrowicz, "Time evolution of the plasma channel at the trail of a self-guided IR femtosecond laser pulse in air," Optics Commun. 181, 123-127 (2000) 16. H. Schillinger, R. Sauerbrey, "Electrical conductivity of long plasma channels in air generated by selfguided femtosecond laser pulses," Appl. Phys. B 68, 753-756 (1999) 17. D. Strickland, G. Mourou, "Compression of amplified chirped optical pulses," Opt. Commun. 56, 219-221 (1985) #89041 556-558 (1968). Note that the radius considered in the classical writing of Marburger's formula is the half-width at ...

Transition from Plasma-Driven to Kerr-Driven Laser Filamentation

“…This finding provides a better understanding of filamentation, and therefore allows to improve its modelling. It further confirms the relevance of the measured HOKE [8,9], with implications ranging from spectral broadening in optical fibers [25] to the generation of few-cycle pulses [26], atmospheric applications [5][6][7], or fermionic light [27].…”

“…Filamentation [1][2][3][4] is a self-guided propagation regime typical of high-power lasers, offering spectacular potential applications [5] like rainmaking [6] and lightning control [7]. We recently challenged its long-established mechanism by measuring the higher order Kerr effect (HOKE) in gases, implying that the non-linear refractive index must be written as ∆n Kerr = n 2j I j , where the non-linear indices n 2j are related to the (2j + 1) th electric susceptibility χ (2j+1) .…”

Higher-order Kerr effects improve quantitative modelling of harmonics generation and laser filamentation

“…This finding confirms that our understanding of laser filamentation has to be updated, which will in particular impact the determination of the optimal conditions for the potential applications [2,15] of laser filamentation, like cloudmaking [16] and lightning control [17].…”

“…Laser filamentation [1,2] is due to a dynamic balance between self-focusing by the Kerr effect, and self-defocusing non-linearities of higher orders. While the contribution of the laser-generated plasma to the self-defocusing has been identified more than a decade ago, the contribution of the higherorder Kerr effect (HOKE) [3,4] to self-defocusing is still actively debated.…”

Triggering, guiding and deviation of long air spark discharges with femtosecond laser filament

“…A discharge obtained with a positive polarity on the HV electrode corresponds to the propagation of an ascending negative leader, and vice versa. As a consequence of the differences between negative and positive leader characteristics and propagation speed, [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] results obtained with positive and negative polarities are quite different. Estimation of the negative discharge velocity based on the delay between the laser and the spark gives V -= 2.5x10 6 m/s, in good agreement with previously reported values for laser guided negative leader velocities.…”