Particle and wave dynamics of nonlocal solitons in external potentials

• Published in: Physics letters. A Vol. 518; p. 129683
• Main Authors: Koutsokostas, G.N., Moseley, I., Horikis, T.P., Frantzeskakis, D.J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.09.2024
• Subjects: Defect modes; External potentials; Nonlocal media; Solitons; Nonlocal media; Defect modes; External potentials; Solitons
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2024.129683

We study nonlocal bright solitons subject to external spatially nonuniform potentials. If the potential is slowly varying on the soliton scale, we derive analytical soliton solutions behaving like Newtonian particles. If the potential has the form of an attractive delta-like point defect, we identify different dynamical regimes, defined by the relative strength of the nonlocality and the point defect. In these regimes, the soliton can be trapped at the defect's location, via a nonlinear resonance with a defect mode –which is found analytically– reflected by or transmitted through the defect, featuring a wave behavior. Our analytical predictions are corroborated by results of direct numerical simulations. •This study analyzes nonlocal bright solitons in varying and point defect potentials, confirming soliton behavior like Newtonian motion.•Asymptotic regimes are identified based on defect strength vs. nonlocal nonlinearity. Solitons show wave dynamics, defect modes, or local NLS behavior.•Our methodology offers a rather universal perspective on the particle-wave duality of nonlocal solitons and is able to capture the analytical soliton solutions of the relative problem.