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Generalized multi-dimensional conservation lawsfor stimulated Raman and Brillouin scattering ina density gradient

POSTER

Abstract

Generalized local and multi-dimensional conservation laws for action, energy, momentum, and angular momentum are derived for stimulated Raman (SRS)

and Brillouin scattering (SBS) in a density gradient within the paraxial ray approximation. A Lagrangian density is found that reproduces the well known envelop equations for SRS and SBS in density gradients in the absence of damping. The symmetry properties of the Lagrangian density are used to obtain local conservation laws for quantities that can easily be identified as the total action, energy, momentum, and orbital angular momentum from each wave. The conservations laws reduce to the one dimensional Manley-Rowe and frequency and wavenumber matching conditions. For pure Laguerre Gaussian profiles the conservation laws for orbital angular momentum

reduce to azimuthal harmonic number matching. Additionally, possible applications for the conservation laws are discussed.

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Presenters

  • Vijay S Patel

    UCLA Foundation

Authors

  • Vijay S Patel

    UCLA Foundation