The Evolution of Lorentz–Gauss Breathers Induced by Off-Waist Incidence

Abstract

We investigate the propagation of Lorentz–Gauss beams (LGBs) for the case of the off-waist incident condition in strongly nonlocal nonlinear media (SNNM) and derive the analytical expression describing the beam width evolution of LGBs. We found that the beam width of LGBs cannot remain invariant and always varies periodically like a breather for the off-waist incident condition, even when the input power of LGBs is equal to the critical input power, which is much different from that for the on-waist incident condition. Also we provide the evolution of the curvature radius of LGBs for the off-waist incident condition, and it is the cause of Lorentz–Gauss breather formation. Numerical simulations are performed to show the propagation characteristics.