Emission characteristics of bulk aerosols excited by externally focused femtosecond filaments

Abstract

The bulk aerosol emissions excited by externally focused femtosecond laser filaments are characterized using time-resolved plasma imaging and spectroscopy. Images of N2 and N2+ plasma fluorescence are used to characterize the filament dimensions. Emission profiles from bulk Sr aerosols are studied, showing that several localized emission regions in the filament begin to develop for lower repetition rates and higher pulse energies. Plasma temperature and electron density profiles are determined using particle emissions along the length of short- and long-focused filaments, and results are compared for on-axis and side-collected spectra. The use of on-axis collection enables the sampling of light emitted over the entire length of the filament; however, the necessary back-propagation of light makes on-axis collection susceptible to self-absorption as the optical path is extended through the filament plasma column formed in bulk aerosols.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 11, 2023
Source ID
10.1364/oe.495456

Entities

People

  • Igor Jovanovic
  • J. Borrero
  • Kyle C. Hartig
  • Kyle S. Latty
  • Megan L. Burger

Organizations

  • Defense Threat Reduction Agency
  • National Nuclear Security Administration
  • National Science Foundation
  • University of Florida
  • University of Michigan

Tags

Fields of Study

  • Physics

Readers

  • Aerosol Science/Aerosol Physics
  • Plasma Physics / Magnetohydrodynamics
  • Reinforced Composite Materials

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Microelectronics