Self-trapped laser beams in plasma

Abstract
A moment theory for the nonlinear quasi‐optical equation with saturation is applied to self‐trapped laser beams in plasma for the ponderomotive nonlinearity. The results differ quantitatively from those obtained form the paraxial ray theory but do agree qualitatively in that there is a minimum beam radius of order cp, a threshold ’’critical’’ power, no upper limit to the power that can be transmitted, and the self‐trapped beams are stable.