Asymmetric impact of higher order diffraction on narrow beam dynamics in nonlocal nonlinear media

The present communication presents the asymmetric impact of different higher-order diffractions on the propagation dynamics, stability analysis, and modulation instability of a narrow Gaussian beam in a nonlocal nonlinear medium. The system equation, which is a nonlocal nonlinear Schrödinger equation, has been solved analytically by the Lagrange variational method as well as numerically using the split-step-Fourier method. The effect of higher order diffraction on beam propagation parameters, critical energy of soliton formation, and potential energy of the system has been highlighted. Linear stability analysis of the system’s governing equation has been performed to identify the parametric space for various classes of equilibrium points against small perturbations. Subsequently, the modulation instability has been investigated and the effect of higher order diffraction has been highlighted.