Orbital Stability of Optical Solitons in 2d
Sergio Moroni
TL;DR
The paper studies orbital stability of ground states for a Schrödinger–Poisson system in two dimensions, modeling optical solitons in nonlocal nematic media. It develops a spectral-coercivity framework based on the second variation of the action around ground states, handling symmetry and nonlocal nonlinearities to prove orbital stability for almost every mass and frequency, with a complementary variational stability result via concentration-compactness. Existence of ground states for every frequency in $(0,1)$ is established through a Nehari-manifold variational approach using a modified energy $E_\sigma$, while a detailed decay analysis shows exponential localization of the stationary profiles. Together, these results provide a rigorous foundation for the stability and structure of optical solitons in nonlocal media and extend the variational analysis to coupled Schrödinger–Poisson systems.
Abstract
We present a stability result for ground states of a Schrödinger-Poisson system in $(2+1)$ dimension, modelling the propagation of a light beam through a liquid crystal with nonlocal nonlinear response. The core of the proof is a coercivity bound on the second derivative of the action, where non scaling nonlinearities and the coupled system present the major difficulties. In addition we prove existence of a ground state with frequency $σ$ for any $σ\in (0,1)$ as a minimal point over an appropriate Nehari manifold.
