No Arabic abstract
In this paper we study the existence and the instability of standing waves with prescribed $L^2$-norm for a class of Schrodinger-Poisson-Slater equations in $R^{3}$ %orbitally stable standing waves with arbitray charge for the following Schrodinger-Poisson type equation label{evolution1} ipsi_{t}+ Delta psi - (|x|^{-1}*|psi|^{2}) psi+|psi|^{p-2}psi=0 % text{in} R^{3}, when $p in (10/3,6)$. To obtain such solutions we look to critical points of the energy functional $$F(u)=1/2| triangledown u|_{L^{2}(mathbb{R}^3)}^2+1/4int_{mathbb{R}^3}int_{mathbb{R}^3}frac{|u(x)|^2| u(y)|^2}{|x-y|}dxdy-frac{1}{p}int_{mathbb{R}^3}|u|^pdx $$ on the constraints given by $$S(c)= {u in H^1(mathbb{R}^3) :|u|_{L^2(R^3)}^2=c, c>0}.$$ For the values $p in (10/3, 6)$ considered, the functional $F$ is unbounded from below on $S(c)$ and the existence of critical points is obtained by a mountain pass argument developed on $S(c)$. We show that critical points exist provided that $c>0$ is sufficiently small and that when $c>0$ is not small a non-existence result is expected. Concerning the dynamics we show for initial condition $u_0in H^1(R^3)$ of the associated Cauchy problem with $|u_0|_{2}^2=c$ that the mountain pass energy level $gamma(c)$ gives a threshold for global existence. Also the strong instability of standing waves at the mountain pass energy level is proved. Finally we draw a comparison between the Schrodinger-Poisson-Slater equation and the classical nonlinear Schrodinger equation.
In this paper we establish the orbital stability of standing wave solutions associated to the one-dimensional Schrodinger-Kirchhoff equation. The presence of a mixed term gives us more dispersion, and consequently, a different scenario for the stability of solitary waves in contrast with the corresponding nonlinear Schrodinger equation. For periodic waves, we exhibit two explicit solutions and prove the orbital stability in the energy space.
We study the instability of standing-wave solutions $e^{iomega t}phi_{omega}(x)$ to the inhomogeneous nonlinear Schr{o}dinger equation $$iphi_t=-trianglephi+|x|^2phi-|x|^b|phi|^{p-1}phi, qquad inmathbb{R}^N, $$ where $ b > 0 $ and $ phi_{omega} $ is a ground-state solution. The results of the instability of standing-wave solutions reveal a balance between the frequency $omega $ of wave and the power of nonlinearity $p $ for any fixed $ b > 0. $
We are going to study the standing waves for a generalized Choquard equation with potential: $$ -ipartial_t u-Delta u+V(x)u=(|x|^{-mu}ast|u|^p)|u|^{p-2}u, hbox{in} mathbb{R}timesmathbb{R}^3, $$ where $V(x)$ is a real function, $0<mu<3$, $2-mu/3<p<6-mu$ and $ast$ stands for convolution. Under suitable assumptions on the potential and appropriate frequency $omega$ , the stability and instability of the standing waves $u=e^{i omega t}varphi(x)$ are investigated .
This article concerns the fractional elliptic equations begin{equation*}(-Delta)^{s}u+lambda V(x)u=f(u), quad uin H^{s}(mathbb{R}^N), end{equation*}where $(-Delta)^{s}$ ($sin (0,,,1)$) denotes the fractional Laplacian, $lambda >0$ is a parameter, $Vin C(mathbb{R}^N)$ and $V^{-1}(0)$ has nonempty interior. Under some mild assumptions, we establish the existence of nontrivial solutions. Moreover, the concentration of solutions is also explored on the set $V^{-1}(0)$ as $lambdatoinfty$.
This paper is devoted to study the existence and multiplicity solutions for the nonlinear Schrodinger-Poisson systems involving fractional Laplacian operator: begin{equation}label{eq*} left{ aligned &(-Delta)^{s} u+V(x)u+ phi u=f(x,u), quad &text{in }mathbb{R}^3, &(-Delta)^{t} phi=u^2, quad &text{in }mathbb{R}^3, endaligned right. end{equation} where $(-Delta)^{alpha}$ stands for the fractional Laplacian of order $alphain (0,,,1)$. Under certain assumptions on $V$ and $f$, we obtain infinitely many high energy solutions for eqref{eq*} without assuming the Ambrosetti-Rabinowitz condition by using the fountain theorem.