The uniqueness and concentration behavior of solutions for a nonlinear fractional Schrödinger system
Chungen Liu, Zhigao Zhang, Jiabin Zuo
TL;DR
The study analyzes a two-component nonlinear fractional Schrödinger system on $\mathbb{R}$ with attractive intra- and interspecies interactions under an $L^2$-mass constraint. By formulating a constrained energy minimization problem, it proves uniqueness of nonnegative minimizers for small interaction parameters via the implicit function theorem and derives detailed concentration behavior as the total interaction strength approaches a critical value, with blow-up occurring at the flattest minima of the trapping potentials. Sharp energy and $L^4$-norm estimates are established, showing a precise blow-up rate and linking the limiting profiles to the ground state of the associated limit equation. The rescaled minimizers converge to the classical ground state $Q$ up to translation and dilation, providing a rigorous description of mass concentration and symmetry-breaking phenomena in this nonlocal multi-component Bose-Einstein condensate model. These results contribute to the understanding of nonlocal, normalized solutions and their concentration dynamics under competing interactions and trapping landscapes.
Abstract
The paper is concerned with a nonlinear system of two coupled fractional Schrödinger equations with both attractive intraspecies and attractive interspecies interactions in $\mathbb{R}$. By analyzing an associated $L^2$-constrained minimization problem, the uniqueness of solutions to this system is proved via the implicit function theorem. Under a certain type of trapping potential, by establishing some delicate energy estimates, we present a detailed analysis on the concentration behavior of the solutions as the total strength of intraspecies and interspecies interactions tends to a critical value, where each component of the solutions blows up and concentrates at a flattest common minimum point of the associated trapping potentials. An optimal blow-up rate of solutions to the system is also given.
