Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing
Abstract
Probing remote matter with laser light is a ubiquitous technique used in circumstances as diverse as laser-induced breakdown spectroscopy andbarcode 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 thedistance of the target. This spot size has a lower bound determined by the diffraction limit of classical optics. However, amplified femtosecondlaser pulses generate intensity sufficient to modify the refractive index of the ambient air and undergo self-focusing. This self-focusing effectleads to the generation of highly intense laser filaments which maintain their intensity and small sub-millimeter diameter size at distances wellbeyond the classical Rayleigh length. Such intensity provides the capability of remote scanning, imaging, sensing, and spectroscopy withenhanced spatial resolution. We describe a technique for generating filaments with a femtosecond regenerative chirped-pulse amplifier, and forusing the resulting filament to conduct imaging and spectroscopic measurements at remote distances of at least several meters.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 25, 2019
- Accession Number
- AD1104070
Entities
People
- Alexei Sokolov
- Benjamin D. Strycker
- Kai Wang
- Marlan Scully
- Matthews M. Springer
Organizations
- Texas A&M University