Processing math: 0%

数学物理学报, 2023, 43(4): 1062-1072

含混合项的拟线性Schrödinger方程的正规化基态解

归坤明,, 陶虹杉,, 杨俊,*

华南理工大学数学学院 广州 510640

Normalized Ground States for the Quasi-linear Schrödinger Equation with Combined Nonlinearities

Gui Kunming,, Tao Hongshan,, Yang Jun,*

School of Mathematics, South China University of Technology, Guangzhou 510640

通讯作者: *杨俊, E-mail: yangjun@scut.edu.cn

收稿日期: 2022-06-17   修回日期: 2023-01-12  

基金资助: 广东省自然科学基金(2018A0303130196)

Received: 2022-06-17   Revised: 2023-01-12  

Fund supported: NSF of Guangdong Province(2018A0303130196)

作者简介 About authors

归坤明,E-mail:guikunming@qq.com;

陶虹杉,sora1924@outlook.com

摘要

该文研究了一类含混合项拟线性Schrödinger方程正规化基态解的存在性. 推广了文献[1-2]中的结果, 与他们研究的情形相比, 该文中方程对应能量泛函的结构更加复杂.

关键词: 正规化解; 拟线性Schrödinger方程; 摄动法

Abstract

In this paper, we mainly investigate the existence of normalized ground states for the Schrödinger equation with combined nonlinearities. Our results extend those reported in [1-2]. Compared with the case they studied, the structure of the energy function correspongding to the equation in this paper is more complex.

Keywords: Normalized solutions; Quasi-linear Schrödinger equation; Perturbation method

PDF (345KB) 元数据 多维度评价 相关文章 导出 EndNote| Ris| Bibtex  收藏本文

本文引用格式

归坤明, 陶虹杉, 杨俊. 含混合项的拟线性Schrödinger方程的正规化基态解[J]. 数学物理学报, 2023, 43(4): 1062-1072

Gui Kunming, Tao Hongshan, Yang Jun. Normalized Ground States for the Quasi-linear Schrödinger Equation with Combined Nonlinearities[J]. Acta Mathematica Scientia, 2023, 43(4): 1062-1072

1 引言

拟线性Schrödinger方程

iϕt+Δϕ+ϕΔ(|ϕ|2)+f(|ϕ|2)ϕ=0,(t,x)(0,+)×RN
(1.1)

可以用来描述等离子体物理、非线性光学和流体力学中的一些现象, 参见文献[3-5]等. 这里ϕ 表示波函数, N.

考虑方程(1.1)形如\phi_\lambda(t,x)=u_\lambda(x)e^{-i\lambda t}的驻波解, 其中\lambda \in \mathbb{R} 为固定的参数. 代入方程(1.1)式可得一类含变分结构的拟线性方程

\begin{equation} -\Delta u -u\Delta(u^2)=\lambda u+g(u),uad x\in \mathbb{R} ^N,\end{equation}
(1.2)

其中g(u)=f(u^2)u.

对于给定的\lambda, 关于方程(1.2)非平凡解的存在性, 目前已有大量的结果, 如文献[6,7]. 本文关注的是方程(1.2)正规化解的存在性, 即解u 满足(1.2)且有

\begin{equation} \int_{\mathbb{R} ^N}\left|u\right|^2=a,\end{equation}
(1.3)

其中a>0是固定的常数.

关于方程(1.2)正规化解的研究, 近期吸引了很多学者的关注. 当g(u)=|u|^{p-2}u时, 文献[8]考虑了在限制(1.3)式下, 极小解的存在和不存在性. 准确地讲, 作者证明了, 当2<p<2+\frac{4}{N}时, 限制极小m(a)<0,\ \forall a>0; 当2+\frac{4}{N}\leqslant p<4+\frac{4}{N}时, 存在一个常数C(p,N)>0, 使得当0<a<C(p,N)时, m(a)=0且不可达; 当a>C(p,N) 时, m(a)<0 且可达. 借助于限制上的山路定理和摄动方法[9], 文献[10]进一步考虑了2+\frac{4}{N}\leqslant p<4+\frac{4}{N} 时, 多重解的存在性. 近期, 在文献[1]中, 同样采取摄动方法, 得到了L^2临界, 即p=4+\frac{4}{N} 时, 基态解的存在性和不存在性, 以及L^2 超临界, 即4+\frac{4}{N}<p<\frac{N+2}{N-2}时, 解的存在性. 另外,文献[11]研究了方程(1.2)含有位势项V(x)u的情况. 当2<p<4+\frac{4}{N}时, 他们得到了基态解在L^2临界时的存在性,以及q趋于L^2临界时的渐近行为.

本文考虑方程(1.2)的一种混合情形, 即非线性项包含L^2 临界和次临界指数的情形

\begin{equation} -\Delta u -u\Delta(u^2)=\lambda u+\mu|u|^{q-2}u+|u|^{p-2}u,uad x\in \mathbb{R} ^N,\end{equation}
(1.4)

其中\lambda,\mu\in \mathbb{R},\ 2<q<p=\overline{p}\triangleq 4+\frac{4}{N},\ N\geq 3. 这种情况是文献[2]关于NLS方程结果在拟线性Schrödinger方程上的推广, 也是文献[1]中拟线性Schrödinger方程非线性项的推广. 需要指出的是, 此时方程(1.4)对应能量泛函的结构更复杂, 故要进行更精细的估计.

定义 1.1\tilde{u}是方程(1.4)式在S_a上的基态解, 若它是方程(1.4)在S_a 上有最小能量的解

{\rm d}E_\mu|_{S_a}(\tilde{u})=0,uad E_\mu(\tilde{u})=\mathop{\inf}\limits_{u\in S_a}\{E_\mu(u)|{\rm d}E_\mu|_{S_a}(u)=0\},

其中泛函为

\begin{equation} E_\mu(u)=\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\frac{\mu}{q}\int_{\mathbb{R} ^N}\left|u\right|^q-\frac{1}{p}\int_{\mathbb{R} ^N}\left|u\right|^p\end{equation}
(1.5)

限制在L^2

u\in S_a\triangleq\left\{u\in X\left|\int_{\mathbb{R} ^N}\left|u\right|^2=a\right.\right\}

上, 这里

X\triangleq\left\{u\in H^1(\mathbb{R} ^N)\left|\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2<+\infty\right.\right\}.

并记

m(a,\mu)\triangleq\mathop{\inf}\limits_{u\in S_a}E_\mu(u).

同时令a^*=\left|Q_{\overline{p}}\right|_1为临界质量(具体定义见下节).

下面是本文的主要结论.

定理 1.1a<a^*时,有

(i)当指标处于以下范围之一

\begin{eqnarray*} \left\{ \begin{array}{lll} \mu>0, 2<q<2+\frac{4}{N},\\[3mm] \mu>\mu_1, q=2+\frac{4}{N},\\[3mm] \mu>\mu_2, 2+\frac{4}{N}<q<4+\frac{4}{N} \end{array}\right. \end{eqnarray*}

时, 有-\infty<m(a,\mu)<0, 此时下确界可达. 其中\mu_1,\mu_2>0为常数, 其值见(3.2),(3.3)式. 记达到函数为\tilde{u}, 则\exists \lambda_a <0, 使(\lambda_a,\tilde{u})是方程(1.4)的基态解.

(ii)当\mu<0时, 有m(a,\mu)=0, 此时方程(1.4)无解.

定理 1.2a=a^*时,有

(i) 当\mu>0,\ 2<q<2+\frac{4}{N} 时, 有-\infty<m(a,\mu)<0, 此时下确界可达. 记达到函数为\tilde{u}, 则\exists \lambda_a <0, 使(\lambda_a,\tilde{u}) 是方程(1.4)的基态解.

(ii) 当指标处于以下范围之一

\begin{eqnarray*} \left\{ \begin{array}{lll} \mu>\mu_3,& & q=2+\frac{4}{N},\\[3mm] \mu>0,& & 2+\frac{4}{N}<q<4+\frac{4}{N} \end{array}\right. \end{eqnarray*}

时, 有m(a,\mu)=-\infty, 其中\mu_3>0为常数, 其值见(5.1)式.

(iii) 当\mu<0时, 有m(a,\mu)=0, 此时方程(1.4)无解.

定理 1.3a>a^*时, 有m(a,\mu)=-\infty.

研究该问题的首要困难在于: 能量泛函中如下的积分项\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2H^1(\mathbb{R} ^N)上不可微, 受文献[9,10]的启发, 本文采取添加扰动项的办法解决该问题.另一方面, 相比于不含拟线性项的问题[2], 本文中指标p,q取值范围更大. 而泛函下确界的性质, 以及原问题的可解性, 与p,q,\mu的取值密切相关, 因此需要细致地划分多种情形.

注 1.1 本文用\left| \cdot \right|_p表示L^p(\mathbb{R} ^N)空间中的通常范数,即\left|u\right|_p \triangleq \left(\int_{\mathbb{R} ^N}\left|u\right|^p\right)^{\frac{1}{p}}. C, C_1, C_2,\cdots通常指的是一些变化的常数, 对主要结论没有影响.

2 预备

为了证明主要结论, 需要用到下列的Gagliardo-Nirenberg不等式.

引理 2.1 (文献[Gagliardo Nirenberg不等式]) 设2<p<2(2^*), u\in L^1(\mathbb{R} ^N)\nabla u\in L^2(\mathbb{R} ^N), 则有

\begin{equation} \int_{\mathbb{R} ^N}\left|u\right|^{\frac{p}{2}}\leqslant \frac{C(p,N)}{\left|Q_p\right|^{\frac{p-2}{N+2}}_1} \left(\int_{\mathbb{R} ^N}\left|u\right|\right)^{\eta_p} \left(\int_{\mathbb{R} ^N}\left|\nabla u\right|^2\right)^{\frac{p\gamma_p}{N+2}},\end{equation}
(2.1)

其中

\gamma_p=\frac{N(p-2)}{2p},uad \eta_p=\frac{4N-p(N-2)}{2(N+2)}

C(p,N)=\frac{p(N+2)}{[4N-p(N-2)]^{\frac{4-N(p-4)}{2(N+2)}}[2N(p-2)]^{\frac{p\gamma_p}{N+2}}},

Q_p为下列问题的唯一非负径向对称解

\begin{eqnarray*}\left\{ \begin{array}{lll} -\Delta u+1=\lambda u^{\frac{p}{2}-1},& & x\in B_R, \ \ R>0,\ \ \mbox{supp} u\subset \subset B_R,\\ u=\frac{\partial u}{\partial n}=0,& & x\in \partial B_R. \end{array}\right.\end{eqnarray*}

u\in X, 在不等式(2.1)中用u^2替换u, 可得

\begin{equation} \frac{1}{p}\int_{\mathbb{R} ^N}\left|u\right|^p\leqslant K(p,N)\left(\int_{\mathbb{R} ^N}\left|u\right|^2\right)^{\eta_p}\left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\right)^{\frac{p\gamma_p}{N+2}},\end{equation}
(2.2)

其中K(p,N)=\frac{C(p,N)}{p\left|Q_p\right|^{\frac{p-2}{N+2}}_1}\cdot4^{\frac{p\gamma_p}{N+2}}.

p=\overline{p}时, (2.2)式化为

\begin{equation}\label{cGN} \frac{1}{\overline{p}}\int_{\mathbb{R} ^N}\left|u\right|^{\overline{p}}\leqslant \left(\frac{a}{\left|Q_{\overline{p}}\right|_1}\right)^{\frac{2}{N}}\left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\right).\end{equation}
(2.3)

于是定义a^*=\left|Q_{\overline{p}}\right|_1为临界质量. 且由文献[11,引理2.1]知, Q_p与临界质量还具有如下关系

\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{\overline{p}}{2}}=(N+1)a^*,uad \int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}\right|^2=Na^*.

下面以\mu=0的情况为例, 观察临界质量如何影响泛函结构. 由(1.5)和(2.2)式得

\begin{eqnarray*} E_0(u)\geqslant \frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-K(p,N)a^{\eta_p} \left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\right)^{\frac{p\gamma_p}{N+2}},\end{eqnarray*}

注意到

\begin{eqnarray*} \frac{p\gamma_p}{N+2}\left\{ \begin{array}{lll} <1, 2 <p<\overline{p},\\ =1, p =\overline{p},\\ >1, \overline{p} <p<2(2^*). \end{array}\right.\end{eqnarray*}

显然, 当2<p<\overline{p}时, E_0S_a上有下界; 当p=\overline{p},\ a\leqslant a^*时,有

1-K(\overline{p},N)a^{\lambda_{\overline{p}}}=1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\geqslant 0.

E_0S_a上也有下界.

下面说明其它情形时, E_0(u)S_a上无下界. 为此, 对于\forall s\in \mathbb{R},\ u\in S_a, 引入保L^2 范数的变换

(s\star u)(x)\triangleq e^{\frac{Ns}{2}}u(e^sx)uad \mbox{a.e. } x\in \mathbb{R} ^N,

直接计算得

E_0(s\star u)=\frac{e^{2s}}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+e^{(N+2)s}\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\frac{e^{p\gamma_p s}}{p}\int_{\mathbb{R} ^N}\left|u\right|^p,

显然, 当p>\overline{p}时, \lim\limits_{s\rightarrow +\infty}E_0(s\star u)=-\infty;

p=\overline{p},\ a>a^*时, 由(2.3)式等号可达知, 存在\overline{u}\in S_a使

\frac{1}{\overline{p}}\int_{\mathbb{R} ^N}\left|\overline{u}\right|^{\overline{p}}>\int_{\mathbb{R} ^N}\left|\overline{u}\right|^2\left|\nabla \overline{u}\right|^2,

\lim\limits_{s\rightarrow +\infty}E_0(s\star \overline{u})=-\infty.

3 基态解的存在性

在引言中提到, 拟线性项对应的能量泛函可微性的不足是寻找问题(1.4)基态解的首要阻碍. 为此, 本节采取添加扰动项的方式解决该问题. 且由于证明过程十分相似, 本节将一并说明定理1.1和1.2(i).

E_\mu^\delta(u)=\frac{\delta}{4}\int_{\mathbb{R} ^N}\left|\nabla u\right|^4+E_\mu(u),uad \tilde{m}(a,\mu)\triangleq \mathop{\inf}\limits_{u\in \tilde{S}_a}E_\mu^\delta(u),

其中0<\delta \leqslant 1.

u\in \tilde{S}_a\triangleq \left\{u\in \tilde{X}\left|\int_{\mathbb{R} ^N}\left|u\right|^2=a\right.\right\},

其中\tilde{X}\triangleq W^{1,4}(\mathbb{R} ^N)\cap W^{1,2}(\mathbb{R} ^N)是自反的Banach空间, 具有如下范数

\left|\left|u\right|\right|_{\tilde{X}}=\left|\left|u\right|\right|_{W^{1,2}}+\left|\left|u\right|\right|_{W^{1,4}}.

同时由文献[9]知, E_\mu^\delta \in C^1(\tilde{X}).

引理 3.1 在定理1.11.2的(i)所述的指标范围内, 有-\infty<\tilde{m}(a,\mu)<0.

证 当a<a^*时, 利用(2.2)式和Cauchy不等式, 注意到\frac{q\gamma_q}{N+2}<1, 则对\forall u \in \tilde{S_a}

\begin{eqnarray*} E_\mu^\delta(u)&\geqslant& \frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+\left[1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right]\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\mu K(q,N)a^{\eta_q}\left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\right)^{\frac{q\gamma_q}{N+2}}\\ & \geqslant& \left[1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right]\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\mu K(q,N)a^{\eta_q}\left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\right)^{\frac{q\gamma_q}{N+2}}\\ &\geqslant& -C. \end{eqnarray*}

a=a^*,\ 2<q<2+\frac{4}{N}时, 利用Sobolev不等式

\begin{equation} \int_{\mathbb{R} ^N}\left|u\right|^q\leqslant C\left(\int_{\mathbb{R} ^N}\left|u\right|^2\right)^{\frac{q(1-\gamma_q)}{2}}\left(\int_{\mathbb{R} ^N}\left|\nabla u\right|^2\right)^{\frac{q\gamma_q}{2}}=\tilde{C}\left(\int_{\mathbb{R} ^N}\left|\nabla u\right|^2\right)^{\frac{q\gamma_q}{2}}. \end{equation}

注意到\frac{q\gamma_q}{2}<1, 则对\forall u \in \tilde{S_a}

\begin{eqnarray*} E_\mu^\delta(u)&\geqslant& \frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2-\frac{\mu}{q}\int_{\mathbb{R} ^N}\left|u\right|^q\\& \geqslant& \frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2-\frac{\mu C}{q}\left(\int_{\mathbb{R} ^N}\left|\nabla u\right|^2\right)^{\frac{q\gamma_q}{2}}\\ & \geqslant& -C. \end{eqnarray*}

上述C>0u无关, 故总有\tilde{m}(a,\mu)>-\infty.

另一方面, 对于a\leqslant a^*,\ 2<q<2+\frac{4}{N}, 直接计算得

\begin{eqnarray*} E_\mu^\delta(s\star u)&=& \frac{\delta e^{(N+4)s}}{4}\int_{\mathbb{R} ^N}\left|\nabla u\right|^4+\frac{e^{2s}}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2-\frac{\mu e^{q\gamma_qs}}{q}\int_{\mathbb{R} ^N}\left|u\right|^q\\& & +e^{(N+2)s}\left(\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\frac{1}{\overline{p}}\int_{\mathbb{R} ^N}\left|u\right|^{\overline{p}}\right), \end{eqnarray*}

注意到q\gamma_q<2, 将u固定, 将s视为自变量, 上式即可简记为

\begin{eqnarray*} E_\mu^\delta(s\star u)&=& C_1 e^{(N+4)s}+C_2 e^{2s}+C_3 e^{(N+2)s}-C_4 e^{q\gamma_q s}\\& =& Ce^{q\gamma_q s}\left(C_1 e^{(N+4-q\gamma_q)s}+C_2 e^{(2-q\gamma_q)s}+C_3 e^{(N+2-q\gamma_q)s}-1\right), \end{eqnarray*}

注意到

e^{(N+4-q\gamma_q)s}+e^{(2-q\gamma_q)s}+e^{(N+2-q\gamma_q)s}\mathop{\longrightarrow}\limits^{s\rightarrow -\infty}0,

则当s\ll -1充分小时, 有E_\mu^\delta(s\star u)<0.

对于a<a^*,\ q\geqslant 2+\frac{4}{N}, 取

w=\left(\frac{a}{a^*}\right)^{\frac{1}{2}}Q_{\overline{p}}^{\frac{1}{2}},uad w_t=t^{\frac{N}{2}}w(tx),

显然有w,w_t\in \tilde{S_a}, 代入E_\mu^\delta计算得

\begin{eqnarray*} E_\mu^\delta(w_t)&=& \frac{\delta t^{N+4}}{4}\left(\frac{a}{a^*}\right)^2\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^4+\frac{t^2}{2}\frac{a}{a^*}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2+\frac{Na^*t^{N+2}}{4}\left(\frac{a}{a^*}\right)^2\left\{1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right\}\\ && - \frac{\mu t^{q\gamma_q}}{q}\left(\frac{a}{a^*}\right)^{\frac{q}{2}}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{q}{2}}\\& =& t^2\left(\frac{a}{a^*}\right)^2\left[\frac{\delta t^{N+2}}{4}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^4+\frac{1}{2}\frac{a^*}{a}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2+\frac{Na^*t^N}{4}\left\{1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right\} \right. \\ && - \left. \frac{\mu t^{q\gamma_q-2}}{q}\left(\frac{a}{a^*}\right)^{\frac{q}{2}-2}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{q}{2}}\right]\\ & \triangleq& t^2\left(\frac{a}{a^*}\right)^2\varphi(t). \end{eqnarray*}

q=2+\frac{4}{N}时, 有

\begin{eqnarray*} E_\mu^\delta(w_t)&=& \frac{\delta t^{N+4}}{4}\left(\frac{a}{a^*}\right)^2\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^4+\frac{Na^*t^{N+2}}{4}\left(\frac{a}{a^*}\right)^2\left\{1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right\}\\&& + \frac{at^2}{a^*}\left(\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2-\frac{\mu}{2+\frac{4}{N}}\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{1+\frac{2}{N}}\right).\\ \end{eqnarray*}

\begin{equation}\label{mu1} \mu_1=\left(1+\frac{2}{N}\right)\left(\frac{a^*}{a}\right)^{\frac{2}{N}}\frac{\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2}{\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{1+\frac{2}{N}}}, \end{equation}

\mu>\mu_1时,有

\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2-\frac{\mu}{2+\frac{4}{N}}\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{1+\frac{2}{N}}<0.

同理得, 当t\ll -1充分小时, 有E_\mu^\delta(w_t)<0.

q>2+\frac{4}{N}时, 考察\varphi'(t)=0, 即

\begin{eqnarray*}& & \frac{(N+2)\delta t^{N+4-q\gamma_q}}{4}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^4+\frac{N^2a^*t^{N+2-q\gamma_q}}{4}\left\{1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right\}\\ & =& \frac{\mu(q\gamma_q-2)}{q}\left(\frac{a}{a^*}\right)^{\frac{q}{2}-2}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{q}{2}}, \end{eqnarray*}

注意到N+4-q\gamma_q>N+2-q\gamma_q>0>2-q\gamma_q, 则上式左侧关于t\geqslant 00单增到+\infty, 而右侧关于t是正常数. 故存在唯一\overline{t}>0, 使\varphi'(\overline{t})=0, 且\overline{t}\varphi的极小值点.

\varphi(\overline{t})<0

\begin{equation}\mu>\mu_2=\frac{q\overline{t}^{2-q\gamma_q}}{4}\cdot \left(\frac{a}{a^*}\right)^{\frac{4-q}{2}}\cdot\frac{\delta\overline{t}^{N+2}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^4+Na^*\overline{t}^N\left\{1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right\}+2\frac{a^*}{a}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2}{\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{q}{2}}}, \end{equation}

\mu>\mu_2时, E_\mu^\delta(w_{\overline{t}})=\overline{t}^2\left(\frac{a}{a^*}\right)^2\varphi(\overline{t})<0.

上述过程证明了总有\tilde{m}(a,\mu)<0. 综上, 证毕.

注 3.1 若记u^*u的\rm Schwarz对称化,则由文献[8,引理4.3]知

F(u^*)\leqslant F(u)=\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2,

且还有

\int_{\mathbb{R} ^N}\left|u^*\right|^p=\int_{\mathbb{R} ^N}\left|u\right|^p,uad \forall p\in [\overline{p}].

因此在之后的证明中, 若出现E_\mu^\delta的极小化序列, 则始终默认其是\rm Schwarz 对称的.

引理 3.2 任意给定0<\delta \leqslant 1, 设\{u_n\}\subset \tilde{S}_a 满足 E_\mu ^\delta(u_n)\rightarrow \tilde{m}(a,\mu), 则在定理1.11.2的(i)所述的指标范围内, \{u_n\}\subset \tilde{X}有界.

a<a^*时, 由(2.2)式得

\begin{eqnarray*} E_\mu^\delta(u_n)&\geqslant& \frac{\delta}{4}\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4 +\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2+\left[1-\left(\frac{a}{a^*}\right)^{\frac{2}{N}}\right]\int_{\mathbb{R} ^N}\left|u_n\right|^2\left|\nabla u_n\right|^2\\ & &-\mu K(q,N)a^{\eta_q}\left(\int_{\mathbb{R} ^N}\left|u_n\right|^2\left|\nabla u_n\right|^2\right)^{\frac{q\gamma_q}{N+2}}, \end{eqnarray*}

注意到\frac{q\gamma_q}{N+2}<1, 由E_\mu ^\delta(u_n)\rightarrow \tilde{m}(a,\mu)

\int_{\mathbb{R} ^N}\left|u_n\right|^2\left|\nabla u_n\right|^2<C,uad \int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4<C,uad \int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2<C,

\{u_n\}\subset \tilde{X}有界.

a=a^*,\ q<2+\frac{4}{N}时, 由(3.1)式得

E_\mu^\delta(u_n)\geqslant \frac{\delta}{4}\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4 +\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2-\frac{\mu C}{q}\left(\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2\right)^{\frac{q\gamma_q}{2}},

注意到\frac{q\gamma_q}{2}<1, 由E_\mu ^\delta(u_n)\rightarrow \tilde{m}(a,\mu)和(3.1)式得

\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4<C,uad \int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2<C,uad \int_{\mathbb{R} ^N}\left|u_n\right|^q<C,

注意到q<\overline{p}<4^*=\frac{4N}{N-4}, 由Hölder不等式得

\left|u_n\right|_{\overline{p}}\leqslant \left|u_n\right|_q^{1-\alpha}\left|u_n\right|_{4^*}^\alpha<C.

将上述四项有界性直接带入E_\mu^\delta(u_n), 立得\int_{\mathbb{R} ^N}\left|u_n\right|^2\left|\nabla u_n\right|^2<C, 即\{u_n\}\subset \tilde{X}有界.证毕.

引理 3.3a_1,a_2>0满足a_1+a_2=a\leqslant a^*.\tilde{m}(a,\mu)<\tilde{m}(a_1,\mu)+\tilde{m}(a_2,\mu).

任取0<c<a^*,\theta>1使\theta c\leqslant a^*.\{u_n\}\subset \tilde{S_c} 满足E_\mu ^\delta(u_n)\rightarrow \tilde{m}(c,\mu), 直接计算得

\begin{eqnarray*} \tilde{m}(\theta c,\mu)&\leqslant& E_\mu ^\delta(u_n(\theta ^{-\frac{1}{N}}x))\\ &=&\frac{\delta \theta ^{1-\frac{4}{N}}}{4}\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4+\theta ^{1-\frac{2}{N}}\int_{\mathbb{R} ^N}\left(\frac{1}{2}+\left|u_n\right|^2\right)\left|\nabla u_n\right|^2-\frac{\theta}{\overline{p}}\int_{\mathbb{R} ^N}\left|u_n\right|^{\overline{p}}-\frac{\mu\theta}{q}\int_{\mathbb{R} ^N}\left|u_n\right|^q\\ &\leqslant& \theta E_\mu ^\delta(u_n), \end{eqnarray*}

n\rightarrow +\infty, 得\tilde{m}(\theta c,\mu)\leqslant \theta \tilde{m}(c,\mu). 注意到等号成立当且仅当

\lim\limits_{n\rightarrow +\infty}\left(\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4+\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^2+\int_{\mathbb{R} ^N}\left|u_n\right|^2\left|\nabla u_n\right|^2\right)=0,

显然这不可能. 故有

\tilde{m}(\theta c,\mu)<\theta \tilde{m}(c,\mu).

\theta=\frac{a}{a_1}>1,\ c=a_1<a^*, 得\tilde{m}(a_1,\mu)>\frac{a_1}{a}\tilde{m}(a,\mu). 同理, \tilde{m}(a_2,\mu)>\frac{a_2}{a}\tilde{m}(a,\mu). 两式相加即得结论, 证毕.

命题 3.1\{u_n\}\subset \tilde{S}_a满足E_\mu ^\delta(u_n)\rightarrow \tilde{m}(a,\mu). 则在平移意义下, \{u_n\} 存在子列在\tilde{X}中相对紧, 即, \exists \{u_{n_k}\}\subset \{u_n\},\ \{y_k\}\subset \mathbb{R},\ {u}_\delta\in \tilde{S}_a, 使u_{n_k}(x+y_k)\rightarrow{u}_\delta(x)\tilde{X}中.

利用集中紧原理, 以下三条结论有且仅有一条成立

(i)消失性: \forall R>0,

\lim\limits_{n\rightarrow +\infty}\mathop{\sup}\limits_{y\in \mathbb{R} ^N}\int_{B_R(y)}\left|u_n\right|^2=0.

(ii)二分性: \exists a_1\in (0,a),\ \{u_n^1\},\ \{u_n^2\}\subset \tilde{X}有界, 使

\begin{eqnarray*}\left\{ \begin{array}{lll} \left|u_n-(u_n^1+u_n^2)\right|_r\rightarrow 0,uad \forall r\in (2,2(2^*)),uad \left|u_n^1\right|_2\rightarrow a_1,uad \left|u_n^2\right|_2\rightarrow a-a_1,\\ \mbox{dist}(\mbox{supp} u_n^1,\mbox{supp}u_n^2)\rightarrow +\infty,\\[2mm] \liminf\limits_{n\rightarrow +\infty}\int_{\mathbb{R} ^N}\{\left|u_n\right|^2\left|\nabla u_n\right|^2-(\left|u_n^1\right|^2\left|\nabla u_n^1\right|^2+\left|u_n^2\right|^2\left|\nabla u_n^2\right|^2)\}\geqslant 0,\\[3mm] \liminf\limits_{n\rightarrow +\infty}\int_{\mathbb{R} ^N}\{\left|\nabla u_n\right|^2-(\left|\nabla u_n^1\right|^2+\left|\nabla u_n^2\right|^2)\}\geqslant 0,\\[3mm]\liminf\limits_{n\rightarrow +\infty}\int_{\mathbb{R} ^N}\{\left|\nabla u_n\right|^4-(\left|\nabla u_n^1\right|^4+\left|\nabla u_n^2\right|^4)\}\geqslant 0. \end{array}\right. \end{eqnarray*}

(iii)紧性: \exists \{y_k\}\subset\mathbb{R} ^N, 使\forall \epsilon >0,\ \exists R>0, 有

\int_{B_R(y_k)}\left|u_n\right|^2\geqslant a-\epsilon.

若(i)成立, 则由文献[12,引理I.1]知: u_n\rightarrow 0L^r(\mathbb{R} ^N),\forall r\in (2,2(2^*))中. 则\liminf\limits_{n\rightarrow +\infty}E_\mu ^\delta(u_n)\geqslant 0, 与引理3.1矛盾!

若(ii)成立, 则有

\tilde{m}(a,\mu)=\lim\limits_{n\rightarrow +\infty}E_\mu ^\delta(u_n)\geqslant \liminf\limits_{n\rightarrow +\infty}(E_\mu ^\delta(u_n^1)+E_\mu ^\delta(u_n^2))\geqslant \tilde{m}(a_1,\mu)+\tilde{m}(a_2,\mu),

与引理3.3矛盾!

因此必有(iii)成立. 令\tilde{u}_k(x)\triangleq u_{n_k}(x+y_k), 则\tilde{u}_k\rightarrow{u}_\deltaL^2(\mathbb{R} ^N)中且 {u}_\delta \in \tilde{S}_a.

由Hölder不等式和引理3.2, 易得\tilde{u}_k\rightarrow{u}_\deltaL^r(\mathbb{R} ^N),\forall r\in (2,2(2^*))中. 再由Fatou引理得

\tilde{m}(a,\mu)\leqslant E_\mu ^\delta( {u}_\delta)\leqslant \limsup_{n\rightarrow +\infty}E_\mu ^\delta( {u}_k)=\tilde{m}(a,\mu).

\left|\left|\tilde{u_k}\right|\right|_{\tilde{X}}\rightarrow \left|\left|u_\delta\right|\right|_{\tilde{X}}, 证毕.

在本文中, 文献[10]中的定理4.1可写为如下引理.

引理 3.4 给定a>0, 任取\{\delta_n\}\rightarrow 0. 设\rm Schwarz对称序列\{u_n\}\subset \tilde{S_a}\{\lambda_n\}\subset \mathbb{R} 满足

\left|E_\mu ^{\delta_n}(u_n)\right|\leqslant C,uad (E_\mu ^{\delta_n})'(u_n)-\lambda_n u_n=0,uad \forall n\geqslant 1,

其中C>0n无关.

\exists \tilde{u}\in W^{1,2}\cap L^{\infty}(\mathbb{R} ^N)\setminus \{0\},\ \lambda_a \in \mathbb{R} , 使

\lambda_n\rightarrow \lambda_a,uad (E_\mu)'(\tilde{u})-\lambda_a\tilde{u}=0.

特别的, 若\lambda_a<0, 则u_n\rightarrow \tilde{u}W^{1,2}(\mathbb{R} ^N) 中; u_n\nabla u_n\rightarrow \tilde{u}\nabla \tilde{u}L^2(\mathbb{R} ^N)中; \delta_n\int_{\mathbb{R} ^N}\left|\nabla u_n\right|^4\rightarrow 0.\tilde{u}E_\muS_a上的临界点.

定理1.1和1.2的(i)的证明 由命题3.1, 有E_\mu ^\delta(u_\delta)= \tilde{m}(a,\mu), 这里u_\deltaE_\mu^\delta\tilde{S_a}上的临界点, 即(E_\mu ^\delta|_{\tilde{S_a}})'(u_\delta)=0. 由文献[引理3], 这等价于\exists \lambda_\delta \in \mathbb{R} , 使

(E_\mu^\delta)'(u_\delta)-\lambda_\delta u_\delta=0.

任取\{\delta_n\}\rightarrow 0, 记v_n\triangleq u_{\delta_n},\ \lambda_n \triangleq \lambda_{\delta_n}, 则有

\left|E_\mu^{\delta_n}(v_n)\right|=\left|\tilde{m}(a,\mu)\right|\leqslant C,

其中C>0\delta,N无关. 以及

(E_\mu^{\delta_n})'(v_n)-\lambda_n v_n=0,uad \forall n\geqslant 1.

由引理3.4知, \exists \tilde{u} \in W^{1,2}(\mathbb{R} ^N)\cap L^\infty(\mathbb{R} ^N)\setminus \{0\}以及\lambda_a\in \mathbb{R} , 使

\lambda_n\rightarrow \lambda_a,uad (E_\mu)'(\tilde{u})-\lambda_a\tilde{u}=0.

故有Pohozaev恒等式

\begin{equation} \frac{N-2}{N}\left(\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla \tilde{u}\right|^2+\int_{\mathbb{R} ^N}\left|\tilde{u}\right|^2\left|\nabla \tilde{u}\right|^2\right)-\frac{\lambda}{2}\int_{\mathbb{R} ^N}\left|\tilde{u}\right|^2-\frac{1}{\overline{p}}\int_{\mathbb{R} ^N}\left|\tilde{u}\right|^{\overline{p}}-\frac{\mu}{q}\int_{\mathbb{R} ^N}\left|\tilde{u}\right|^q=0, \end{equation}
(3.4)

代入E_\mu(\tilde{u})化简得

0\geqslant \limsup_{n\rightarrow +\infty}E_\mu^{\delta_n}(v_n)\geqslant E_\mu(\tilde{u})=\frac{1}{N}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+\frac{2}{N}\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2+\frac{\lambda_a}{2}\int_{\mathbb{R} ^N}\left|u\right|^2,

显然有\lambda_a<0, 故\tilde{u}E_\muS_a上的临界点, 即为方程(1.4)的基态解.

综上, 定理1.11.2的(i)证毕.

4 问题无解的情形

在引言中提到, 问题(1.4)的可解性既与临界质量有关, 又与扰动系数有关. 本节将说明问题无解的情形, 证明定理1.1的(ii)和定理1.2的(iii).

u是方程(1.4)的解, 则有(3.4)式成立. 又在(1.4)式左右乘u并积分得

\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+4\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\lambda \int_{\mathbb{R} ^N}\left|u\right|^2-\int_{\mathbb{R} ^N}\left|u\right|^{\overline{p}}-\mu \int_{\mathbb{R} ^N}\left|u\right|^q=0,

将上式与(3.4)式联立, 消去\lambda, 并利用(2.2)式得

\begin{eqnarray*} \mu \gamma_q\int_{\mathbb{R} ^N}\left|u\right|^q&=& \int_{\mathbb{R} ^N}\left|\nabla u\right|^2+(N+2)\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\gamma_{\overline{p}}\int_{\mathbb{R} ^N}\left|u\right|^{\overline{p}}\\& \geqslant& \int_{\mathbb{R} ^N}\left|\nabla u\right|^2+(N+2)\Big\{1-(\frac{a}{a^*})^{\frac{2}{N}}\Big\}\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2\\ & \geqslant& 0, \end{eqnarray*}

但显然\mu \gamma_q\int_{\mathbb{R} ^N}\left|u\right|^q<0, 矛盾! 则方程(1.4)无解.

另一方面,利用(2.2)式得, 对\forall u\in \tilde{S_a}

\begin{eqnarray*} E_\mu(s\star u)&\geqslant& \frac{e^{2s}}{2}\int_{\mathbb{R} ^N}\left|\nabla u\right|^2+e^{(N+2)s} \Big\{1-(\frac{a}{a^*})^{\frac{2}{N}}\Big\}\int_{\mathbb{R} ^N}\left|u\right|^2\left|\nabla u\right|^2-\mu \frac{e^{q\gamma_qs}}{q}\int_{\mathbb{R} ^N}\left|u\right|^q\\& >& 0, \end{eqnarray*}

\lim\limits_{s\rightarrow -\infty}E_\mu(s\star u)=0, 故m(a,\mu)=0.

综上, 定理1.1的(ii)和定理1.2的(iii)证毕.

5 泛函无下界的情形

寻找问题(1.4)的基态解, 重点在能量泛函的下确界. 而如果泛函无下界, 则问题的可解性是不明确的. 本节将说明能量泛函无下界的情形, 证明定理1.2的(ii)和定理1.3.

定理1.2的(ii)的证明 对于q=2+\frac{4}{N}, 仿照引理3.1的方法. 这时a=a^*, 故取

w=Q_{\overline{p}}^{\frac{1}{2}},uad w_t=t^{\frac{N}{2}}w(tx),

直接计算得

E_\mu(w_t)=t^2\left(\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2-\frac{\mu}{2+\frac{4}{N}}\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{\frac{q}{2}}\right).

\begin{equation} \mu_3=\left(1+\frac{2}{N}\right)\frac{\int_{\mathbb{R} ^N}\left|\nabla Q_{\overline{p}}^{\frac{1}{2}}\right|^2}{\int_{\mathbb{R} ^N}\left|Q_{\overline{p}}\right|^{1+\frac{2}{N}}}, \end{equation}
(5.1)

\mu>\mu_3时, 有\lim\limits_{t\rightarrow +\infty}E_\mu(w_t)=-\infty.

对于q>2+\frac{4}{N}, 记(2.2)式的达到函数为w, 注意到(2.2)式关于u齐次, 则不妨设w\in S_{a^*}. 直接计算得

E_\mu(s\star w)=\frac{e^{2s}}{2}\int_{\mathbb{R} ^N}\left|\nabla w\right|^2-\mu \frac{e^{q\gamma_qs}}{q}\int_{\mathbb{R} ^N}\left|w\right|^q,

注意到q\gamma_q>2, 显然有\lim\limits_{s\rightarrow +\infty}E_\mu(s\star w)=-\infty.定理1.2的(\romannumeral2)证毕.

定理1.3的证明 由文献[8,定理1.9]知, m(a,0)=-\infty.\exists u_0\in S_a, 使E_0(u_0)<0. 直接计算得

E_\mu(s\star u_0)=e^{(N+2)s}\left(E_0(u_0)-\frac{1}{2}\int_{\mathbb{R} ^N}\left|\nabla u_0\right|^2\right)+\frac{e^{2s}}{2}\int_{\mathbb{R} ^N}\left|\nabla u_0\right|^2-\mu \frac{e^{q\gamma_qs}}{q}\int_{\mathbb{R} ^N}\left|u_0\right|^q,

注意到q\gamma_q<N+2, 显然有\lim\limits_{s\rightarrow +\infty}E_\mu(s\star u_0)=-\infty.定理1.3证毕.

参考文献

Li H W, Zou W M.

Quasilinear Schrödinger equations: ground state and infinitely many normalized solutions

arXiv preprint, 2021, 2101.07574

[本文引用: 4]

Soave N.

Normalized ground states for the NLS equation with combined nonlinearities

J Differ Equ, 2020, 269: 6941-6987

DOI:10.1016/j.jde.2020.05.016      URL     [本文引用: 4]

Borovskii A V, Galkin A L.

Dynamical modulation of an ultrashort high-intensity laser pulse in matter

J Exp Theor Phys, 1993, 77(4): 562-573

[本文引用: 1]

Ritchie B.

Relativistic self-focusing and channel formation in laser-plasma interactions

Phys Rev E, 1994, 50: 687-689

PMID:9962176      [本文引用: 1]

Hasse R W.

A general method for the solution of nonlinear soliton and kink Schrödinger equations

Z Phys B: Condens Matter, 1980, 37: 83-87

[本文引用: 1]

Shen Y T, Wang Y J.

Soliton solutions for generalized quasilinear Schrödinger equations

Nonlinear Anal Theory Methods Appl, 2013, 80: 194-201

DOI:10.1016/j.na.2012.10.005      URL     [本文引用: 1]

Wang Y J, Shen Y T.

Existence and asymptotic behavior of a class of quasilinear Schrödinger equations

Adv Nonlinear Stud, 2018, 18(1): 131-150

DOI:10.1515/ans-2017-6026      URL     [本文引用: 1]

In this paper, we study the quasilinear Schrödinger equation \n \n \n \n \n \n \n -\n \n Δ\n ⁢\n u\n \n \n +\n \n V\n ⁢\n \n (\n x\n )\n \n ⁢\n u\n \n \n -\n \n \n γ\n 2\n \n ⁢\n \n (\n \n Δ\n ⁢\n \n u\n 2\n \n \n )\n \n ⁢\n u\n \n \n =\n \n \n \n |\n u\n |\n \n \n p\n -\n 2\n \n \n ⁢\n u\n \n \n \n \n {-\\Delta u+V(x)u-\\frac{\\gamma}{2}(\\Delta u^{2})u=|u|^{p-2}u}\n \n, \n \n \n \n x\n ∈\n \n ℝ\n N\n \n \n \n \n {x\\in\\mathbb{R}^{N}}\n \n, where \n \n \n \n \n V\n ⁢\n \n (\n x\n )\n \n \n :\n \n \n ℝ\n N\n \n →\n ℝ\n \n \n \n \n {V(x):\\mathbb{R}^{N}\\to\\mathbb{R}}\n \n is a given potential, \n \n \n \n γ\n &gt;\n 0\n \n \n \n {\\gamma&gt;0}\n \n, and either \n \n \n \n p\n ∈\n \n (\n 2\n,\n \n 2\n *\n \n )\n \n \n \n \n {p\\in(2,2^{*})}\n \n, \n \n \n \n \n 2\n *\n \n =\n \n \n 2\n ⁢\n N\n \n \n N\n -\n 2\n \n \n \n \n \n {2^{*}=\\frac{2N}{N-2}}\n \n for \n \n \n \n N\n ≥\n 4\n \n \n \n {N\\geq 4}\n \n or \n \n \n \n p\n ∈\n \n (\n 2\n,\n 4\n )\n \n \n \n \n {p\\in(2,4)}\n \n for \n \n \n \n N\n =\n 3\n \n \n \n {N=3}\n \n. If \n \n \n \n γ\n ∈\n \n (\n 0\n,\n \n γ\n 0\n \n )\n \n \n \n \n {\\gamma\\in(0,\\gamma_{0})}\n \n for some \n \n \n \n \n γ\n 0\n \n &gt;\n 0\n \n \n \n {\\gamma_{0}&gt;0}\n \n, we establish the existence of a positive solution \n \n \n \n u\n γ\n \n \n \n {u_{\\gamma}}\n \n satisfying \n \n \n \n \n \n max\n \n x\n ∈\n \n ℝ\n N\n \n \n \n ⁡\n \n |\n \n \n γ\n μ\n \n ⁢\n \n u\n γ\n \n ⁢\n \n (\n x\n )\n \n \n |\n \n \n →\n 0\n \n \n \n {\\max_{x\\in\\mathbb{R}^{N}}|\\gamma^{\\mu}u_{\\gamma}(x)|\\to 0}\n \n as \n \n \n \n γ\n →\n \n 0\n +\n \n \n \n \n {\\gamma\\to 0^{+}}\n \n for any \n \n \n \n μ\n &gt;\n \n 1\n 2\n \n \n \n \n {\\mu&gt;\\frac{1}{2}}\n \n. Particularly, if \n \n \n \n \n V\n ⁢\n \n (\n x\n )\n \n \n =\n λ\n &gt;\n 0\n \n \n \n {V(x)=\\lambda&gt;0}\n \n, we prove the existence of a positive classical radial solution \n \n \n \n u\n γ\n \n \n \n {u_{\\gamma}}\n \n and up to a subsequence, \n \n \n \n \n u\n γ\n \n →\n \n u\n 0\n \n \n \n \n {u_{\\gamma}\\to u_{0}}\n \n in \n \n \n \n \n \n H\n 2\n \n ⁢\n \n (\n \n ℝ\n N\n \n )\n \n \n ∩\n \n \n C\n 2\n \n ⁢\n \n (\n \n ℝ\n N\n \n )\n \n \n \n \n \n {H^{2}(\\mathbb{R}^{N})\\cap C^{2}(\\mathbb{R}^{N})}\n \n as \n \n \n \n γ\n →\n \n 0\n +\n \n \n \n \n {\\gamma\\to 0^{+}}\n \n, where \n \n \n \n u\n 0\n \n \n \n {u_{0}}\n \n is the ground state of the problem \n \n \n \n \n \n -\n \n Δ\n ⁢\n u\n \n \n +\n \n λ\n ⁢\n u\n \n \n =\n \n \n \n |\n u\n |\n \n \n p\n -\n 2\n \n \n ⁢\n u\n \n \n \n \n {-\\Delta u+\\lambda u=|u|^{p-2}u}\n \n, \n \n \n \n x\n ∈\n \n ℝ\n N\n \n \n \n \n {x\\in\\mathbb{R}^{N}}\n \n.

Colin M, Jeanjean L, Squassina M.

Stability and instability results for standing waves of quasi-linear Schrödingerr equations

Adv Nonlinear Stud, 2010, 23(6): 1353-1385

[本文引用: 3]

Liu X Q, Liu J Q, Wang Z Q.

Quasilinear elliptic equations with critical growth via perturbation method

J Differ Equ, 2013, 254(1): 102-124

DOI:10.1016/j.jde.2012.09.006      URL     [本文引用: 3]

Jeanjean L, Luo T J, Wang Z Q.

Multiple normalized solutions for quasi-linear Schrödingerr equations

J Differ Equ, 2015, 259(8): 3894-3928

DOI:10.1016/j.jde.2015.05.008      URL     [本文引用: 3]

Zeng X Y, Zhang Y M.

Existence and asymptotic behavior for the ground state of quasilinear elliptic equations

Adv Nonlinear Stud, 2018, 18(4): 725-744

DOI:10.1515/ans-2018-0005      URL     [本文引用: 2]

In this paper, we are concerned with the existence and asymptotic behavior of minimizers of a minimization problem related to some quasilinear elliptic equations. Firstly, we prove that there exist minimizers when the exponent q is the critical one \n \n \n \n \n q\n *\n \n =\n \n 2\n +\n \n 4\n N\n \n \n \n \n \n {q^{*}=2+\\frac{4}{N}}\n \n. Then, we prove that all minimizers are compact as q tends to the critical case \n \n \n \n q\n *\n \n \n \n {q^{*}}\n \n when \n \n \n \n a\n &lt;\n \n a\n \n q\n *\n \n \n \n \n \n {a&lt;a_{q^{*}}}\n \n is fixed. Moreover, we find that all the minimizers must blow up as the exponent q tends to the critical case \n \n \n \n q\n *\n \n \n \n {q^{*}}\n \n for any fixed \n \n \n \n a\n &gt;\n \n a\n \n q\n *\n \n \n \n \n \n {a&gt;a_{q^{*}}}\n \n.

Lions P L.

The concentration-compactness principle in the calculus of variations, the locally compact case, part 2

Ann I H Poincare-AN, 1984, 1(4): 223-283

[本文引用: 1]

Berestycki H, Lions P L.

Nonlinear scalar field equations, II existence of infinitely many solutions

Arch Rat Mech AN, 1983, 82: 347-375

DOI:10.1007/BF00250556      URL    

/