Applied Physics B

, Volume 106, Issue 3, pp 529–532

Low- and high-order harmonic generation inside an air filament

  • T. Vockerodt
  • D. S. Steingrube
  • E. Schulz
  • M. Kretschmar
  • U. Morgner
  • M. Kovačev
Article

DOI: 10.1007/s00340-011-4858-8

Cite this article as:
Vockerodt, T., Steingrube, D.S., Schulz, E. et al. Appl. Phys. B (2012) 106: 529. doi:10.1007/s00340-011-4858-8

Abstract

We report on the generation of third-order (TH) and high-order harmonics (HH) directly inside a self-guided femtosecond filament in air. By terminating the filament with a steep density gradient behind a pinhole placed at different distances from the geometric focus, the evolution of the generated radiation is tracked along the nonlinear interaction zone. Spectra are recorded in the visible (VIS), ultraviolet (UV) and extreme ultraviolet (XUV) spectral range under identical conditions. The VIS and UV spectral bandwidth undergoes significant broadening. The input pulse parameters are varied systematically to optimize the TH bandwidth. Recorded spectra show Fourier-limits below 5 fs pulse duration centered at 264 nm wavelength. We observe conversion to HH up to the 25th order and use the HH generation process as a nonlinear probe for the on-axis intensity evolution along the filament.

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • T. Vockerodt
    • 1
    • 2
  • D. S. Steingrube
    • 1
    • 2
  • E. Schulz
    • 1
    • 2
  • M. Kretschmar
    • 1
  • U. Morgner
    • 1
    • 2
  • M. Kovačev
    • 1
    • 2
  1. 1.Institut für QuantenoptikLeibniz Universität HannoverHannoverGermany
  2. 2.QUESTCentre for Quantum Engineering and Space-Time ResearchHannoverGermany