fractional Kundu-Mukherjee-Naskar equation, fractional partial ]differential equations, $ (\frac{G'}{G}) $-expansion method, generalized fractional derivative, optical solitons, dark soliton lattices

Using comparison principles, we examine the asymptotic characteristics of a third-order nonlinear damped neutral differential equation. Our results substantially generalize numerous previously established results as well as drastically improving them. To illustrate the relevance and effectiveness of our results, we use numerical examples.