In this paper, we consider the existence and multiplicity of solutions for the following fractional Laplacian system with logarithmic nonlinearity $$\begin{aligned} {\left\{ \begin{array}{ll} (-\Delta )^{s}u=\lambda h_1(x)u\ln |u|+\frac{p}{p+q}b(x)|v|^{q}|u|^{p-2}u\ \ &{}x\in \Omega , \\ (-\Delta )^t v=\mu h_2(x)v\ln |v|+\frac{q}{p+q}b(x)|u|^p|v|^{q-2}v\ \ &{}x\in \Omega , \\ u=v=0\ \ &{}x\in \mathbb {R}^N{\setminus }\Omega , \end{array}\right. } \end{aligned}$$ where $$s,t\in (0,1),\ N>\max \{2s,2t\}$$ , $$\lambda ,\mu >0$$ , $$2<p+q<\min \{\frac{2N}{N-2s},\frac{2N}{N-2t}\}$$ , $$\Omega \subset \mathbb {R}^N$$ is a bounded domain with Lipschitz boundary, $$h_1,h_2,b\in C(\overline{\Omega })$$ and $$(-\Delta )^{s}$$ is the fractional Laplacian. When $$h_1,h_2,b$$ are positive functions, the existence of ground state solutions for the problem is obtained. When $$h_1,h_2$$ are sign-changing functions and b is a positive function, two nontrivial and nonnegative solutions are obtained. Our results are new even in the case of a single equation.
Read full abstract