State transition dynamics of double-hump bright soliton in the coupled derivative Schrödinger equation

Dated: August 22, 2025) We study double-hump bright solitons in a two-component coupled derivative nonlinear Schrödinger equation relevant to plasma physics. Using the Darboux transformation, we derive exact solutions and classify their intensity profiles. Notably, collisions between double-hump and single-hump bright solitons convert the former into breather-like states. Asymptotic analysis reveals that this transition results from energy mixing between the two components of the DHBS, with the oscillation period governed by its width parameters. We further analyze multiple collisions involving double-hump and single-hump solitons in two distinct velocity configurations. These collisions lead to interactions either between two breather-like states or between a breather-like state and an single-hump soliton, that have not been reported previously. A systematic asymptotic analysis of multi-soliton collisions is provided using Laplace’s theorem and the Vandermonde determinant, allowing explicit derivation of pre-and post-collision soliton states and precise characterization of their initial and final conditions. These rich collision dynamics suggest promising avenues for controlled excitation in plasma physics and ultrashort pulse manipulation.