讲座内容：

The spectral Tur\'an number $\spex(n, F)$ denotes the maximum spectral radius $\lambda(G)$ of an $F$-free graph $G$ of order $n$. In this talk, we will first introduce some relevant background and then present  our results  on $\spex\left(n, C_{2k+1}^{\square}\right)$ for sufficiently large $n$, establishing the unique extremal graph. Here, $C_{2k+1}^{\square}$ is the odd prism, which is the Cartesian product $C_{2k+1} \square K_2$, where the Cartesian product $G \square F$ has vertex set $V(G) \times V(F)$, and edges between $(u_1,v_1)$ and $(u_2,v_2)$ if either $u_1 = u_2$ and $v_1v_2 \in E(F)$, or $v_1 = v_2$ and $u_1u_2 \in E(G)$.