On Schrödinger-Poisson Systems

We discuss some recent results dealing with the existence of bound states of the nonlinear Schrödinger-Poisson system \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left\{ \begin{gathered} - \Delta u + V(x)u + \lambda K(x)\phi (x)u = |u|^{{p - 1}} u, \hfill \\ - \Delta \phi = K(x)u^{2}, \hfill \\ \end{gathered} \right.$$\end{document} as well as of the corresponding semiclassical limits. The proofs are based upon Critical Point theory and Perturbation Methods.