A nonlinear geometrical optics model of angular momentum beams in unmagnetized plasma

In the context of linear optics, optical vortices display a very rich dynamical behavior. Their behavior in nonlinear media (e.g., Kerr media) gives rise to many interesting physical effects, such as the spiraling of vortex solitons¹ and may lead to unique practical applications. We describe an attempt to construct a nonlinear geometrical optics model of the interaction of orbital angular momentum (OAM) carrying optical beams with unmagnetized, inhomogeneous plasma. We approximate the wave-fields of ray families representing OAM beams using standard methods; the wavefield is then used to modify the plasma response. The initial ray families are generated using a Poincare sphere approach recently described by Alonso and Dennis². The potential benefit of using such beams to mitigate various laser-plasma instabilities, such as two-plasmon decay, and cross-beam energy transfer will be discussed.

 

¹ A. S. Desyatnikov in “The Angular Momentum of Light”, D. L. Andrews and M. Babiker (Cambridge University Press, 2013).

² M. A. Alonso and M. R. Dennis, Optica 4, 476 (2017).