Filament-induced breakdown spectroscopy with structured beams

Abstract

Filament-induced ablation represents an attractive scheme for long-range material identification via optical spectroscopy. However, the delivery of laser energy to the target can be severely hindered by the stochastic nature of multiple-filamentation, ionization of ambient gas, and atmospheric turbulence. In order to mitigate some of these adverse effects, we examine the utility of beam shaping for femtosecond filament-induced breakdown spectroscopy with Gaussian and structured (Laguerre-Gaussian, Airy, and Bessel-Gaussian) beams in the nonlinear regime. Interaction of filaments with copper, zinc, and brass targets was studied by recording axially-resolved broadband emission from the filament-induced plasma. The laser-solid coupling efficacy was assessed by inferring thermodynamic parameters such as excitation temperature and electron density. While under our experimental conditions the ablation rate with Gaussian- and Laguerre-Gaussian beams is found to be similar, the Airy and Bessel-Gaussian beams offer the advantage of longitudinally extended working zones. These results provide insights into potential benefits of structuring ultrafast laser beams for standoff sensing applications.

Forty Years of Laser-Induced Breakdown Spectroscopy and Laser and Particle Beams

“…Combined nanosecond-femtosecond [80,81] and femtosecondfemtosecond [82] dual-pulse analysis was also proposed. Te possibility of maintaining the laser beam collimation at very long distances, due to the flamentation/self-focusing efects that characterize the propagation of fs-laser beams in atmosphere [79,[83][84][85], has triggered many innovative applications of stand-of LIBS, including the remote analysis of cultural heritage [86], biological materials [87], geological samples [88], and explosives [89,90].…”

Numerical simulation study on distinguishing nonlinear propagation regimes of femtosecond pulses in fused silica

“…The nonlinear propagation dynamics of structured beams are also crucial both for fundamental physics studies and practical applications, such as laser micromachining 14 , laser spectroscopy 15 , air lasing 16 , and optical waveguide 17 . However, the nonlinear propagation characteristics of femtosecond vortex beams which have a donut-shaped intensity profile, differ significantly from those of Gaussian beams 18 – 20 .…”

Classification of uneven steel samples by laser induced breakdown spectroscopy based on a Bessel beam

“…Polynkin et al 22 proved that a longer plasma channel with uniform distribution could be generated by a Bessel beam. Burger et al 23 also proved that the Bessel beam in filament induced breakdown spectroscopy (FIBS) can produce a longer longitudinal extension of the working area and expand the plasma emission range. Lin et al 24 used a Bessel beam to lengthen the channels of copper plasma in air.…”