Theory and Modeling of Stimulated Raman Scattering

Abstract

A three-dimensional finite difference method is presented for the propagation through a gain medium of beams focused by an astigmatic lens. The method is used for the modeling of a Raman amplifier that uses astigmatic lenses. With this method, the effect of gain focusing on the amplification is studied. The numerical results show a good correspondence with analytical models in the range where these models are applicable. The threshold power of stimulated Raman scattering (SRS) has been calculated for various nondiffraction-limited pump beams using the numerical model. It is shown that the threshold power, for a tightly focused beam, depends on the M squared factor that is related to the pump beam quality. Additionally, the influence of the exact pump beam profile on the threshold is small. Therefore, the M squared factor is a useful parameter for analyzing the experimental threshold. We show that the measured SRS thresholds in methane correspond with the calculated thresholds.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1993
Accession Number
ADA273755

Entities

People

  • J. C. Van Den Heuvel

Organizations

  • Netherlands Organisation for Applied Scientific Research

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Brillouin Scattering
  • Computational Science
  • Computer Simulations
  • Detectors
  • Differential Equations
  • Diffraction
  • Efficiency
  • Laser Beams
  • Laser Resonators
  • Measurement
  • Power
  • Scattering
  • Standards
  • Three Dimensional
  • Two Dimensional
  • Wave Equations
  • Wave Mixing

Fields of Study

  • Engineering
  • Physics

Readers

  • Optical Physics and Photonics.
  • Theoretical Analysis.