Measurements of fluence profiles in femtosecond laser sparks and superfilaments in air
AffiliationUniv Arizona, Coll Opt Sci
MetadataShow full item record
PublisherAMER PHYSICAL SOC
CitationSamsonova, Z., Kartashov, D., Spielmann, C., Bodrov, S., Murzanev, A., Jukna, V., ... & Polynkin, P. (2018). Measurements of fluence profiles in femtosecond laser sparks and superfilaments in air. Physical Review A, 97(6), 063841. https://doi.org/10.1103/PhysRevA.97.063841
JournalPHYSICAL REVIEW A
Rights©2018 American Physical Society
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe investigate the nonlinear propagation of multiterawatt femtosecond laser pulses at 800 nm wavelength in air, under different external focusing conditions. We profile the laser beam in the vicinity of the nonlinear focus using a technique based on the dependence of the single-shot ablation threshold for gold on the angle of incidence of the laser beam on the sample. Under very tight focusing conditions (f number similar to 15) we observe the propagation regime reminiscent of the nanosecond optical breakdown. No clear individual filaments are formed across the beam, and the estimated peak intensity surges to at least 200 TW/cm(2). As the external focusing is loosened to f number similar to 125, we observe the transition to the multifilamentation regime. Distinct individual filaments are formed before the linear focus while the peak intensity reaches similar to 80 TW/cm(2). Once formed, the filaments do not coalesce into a single or few superfilaments as they pass through the focus zone. Our experimental observations are supported by numerical simulations.
VersionFinal published version
SponsorsU.S. Air Force Office of Scientific Research under MURI [FA9550-16-1-0013]; Laserlab-Europe Project [HIJ-FSU002344]; Friedrich-Schiller-Universitat Jena; University of Arizona