The nonlinear fractional relativistic Schrödinger equation: existence, multiplicity, decay and concentration results
arXiv:2003.06155 · doi:10.3934/dcds.2021092
Abstract
In this paper we study the following class of fractional relativistic Schrödinger equations: \begin{equation*} \left\{ \begin{array}{ll} (-Δ+m^{2})^{s}u + V(\varepsilon x) u= f(u) &\mbox{ in } \mathbb{R}^{N}, \\ u\in H^{s}(\mathbb{R}^{N}), \quad u>0 &\mbox{ in } \mathbb{R}^{N}, \end{array} \right. \end{equation*} where is a small parameter, , , , is the fractional relativistic Schrödinger operator, is a continuous potential satisfying a local condition, and is a continuous subcritical nonlinearity. By using a variant of the extension method and a penalization technique, we first prove that, for small enough, the above problem admits a weak solution which concentrates around a local minimum point of as . We also show that has an exponential decay at infinity by constructing a suitable comparison function and by performing some refined estimates. Secondly, by combining the generalized Nehari manifold method and Ljusternik-Schnirelman theory, we relate the number of positive solutions with the topology of the set where the potential attains its minimum value.