A class of one‐dimensional hollow microstructure is described, which was formed by a kinetically controlled crystal growth process. A hexagonal‐phase NaYbF₄ microrod comprising isolated holes along the longitudinal axis was synthesized by a one‐pot hydrothermal method with the assistance of citrate ligands. The structural void feature modulates light intensity across the microrods as a result of interference arising from light scattering and reflection by the inner walls. A single crystal comprising a structural void was doped with upconverting lanthanide ions. Upon near‐infrared excitation of the doped crystal spatially resolvable optical codes were produced.

中文翻译：

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晶体空心微棒，用于选择性增强非线性光致发光

描述了一类一维空心微结构，它是由动力学控制的晶体生长过程形成的。在柠檬酸盐配体的帮助下，通过单锅水热法合成了一个六角形的NaYbF _4微棒，该微棒沿纵轴包含隔离的孔。由于由内壁的光散射和反射引起的干涉，结构空隙特征调节了穿过微棒的光强度。用上转换镧系元素离子掺杂包含结构空隙的单晶。在掺杂晶体的近红外激发下，产生了空间可分辨的光学代码。