A concentration phenomenon for a semilinear Schrödinger equation with periodic self-focusing core

Mónica Clapp, Alberto Saldaña, Andrzej Szulkin

We consider the equation $$-\Delta u+u=Q_{\epsilon }(x)|u{|}^{p-2}u,u\in H^1({\mathbb{R}}^N),$$ where $Q_{\epsilon }$ takes the value $1$ on each ball $B_{\epsilon }(y)$, $y\in\mathbb…