In the article number 1707175, Chennupati Jagadish, Jr‐Hau He, and co‐workers report the excellent optical nonlinearity of CH₃NH₃PbBr₃ perovskite crystals and its relevant applications. The cover shows the strong two‐photon‐absorption‐induced photoluminescence in single crystal CH₃NH₃PbBr₃ that appears in the green spectral region. Such strong two‐photon absorption suggests promising nonlinear optics applications for this material in next‐generation technologies.

中文翻译：

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非线性光学：CH3NH3PbBr3钙钛矿晶体的非线性吸收应用（Adv。Funct。Mater。18/2018）

Chennupati Jagadish，Jr-Hau He及其同事在文章编号1707175中报告了CH ₃ NH ₃ PbBr ₃钙钛矿晶体的出色光学非线性及其相关应用。封面显示了在绿色光谱区域中出现的单晶CH ₃ NH ₃ PbBr ₃中强烈的两光子吸收诱导的光致发光。如此强大的双光子吸收特性表明该材料在下一代技术中具有广阔的应用前景。