Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing. Academic Article uri icon


  • Probing remote matter with laser light is a ubiquitous technique used in circumstances as diverse as laser-induced breakdown spectroscopy and barcode scanners. In classical optics, the intensity that can be brought to bear on a remote target is limited by the spot size of the laser at the distance of the target. This spot size has a lower bound determined by the diffraction limit of classical optics. However, amplified femtosecond laser pulses generate intensity sufficient to modify the refractive index of the ambient air and undergo self-focusing. This self-focusing effect leads to the generation of highly intense laser filaments which maintain their intensity and small sub-millimeter diameter size at distances well beyond the classical Rayleigh length. Such intensity provides the capability of remote scanning, imaging, sensing, and spectroscopy with enhanced spatial resolution. We describe a technique for generating filaments with a femtosecond regenerative chirped-pulse amplifier, and for using the resulting filament to conduct imaging and spectroscopic measurements at remote distances of at least several meters.

published proceedings

  • J Vis Exp

altmetric score

  • 0.25

author list (cited authors)

  • Springer, M. M., Strycker, B. D., Wang, K., Sokolov, A. V., & Scully, M. O.

citation count

  • 1

complete list of authors

  • Springer, Matthews M||Strycker, Benjamin D||Wang, Kai||Sokolov, Alexei V||Scully, Marlan O

publication date

  • April 2019