As atoms and molecules condense to form solids, a crystalline state can emerge with its highly ordered geometry and subnanometric lattice constant. In some physical systems, such as ferroelectric perovskites, a perfect crystalline structure forms even when the condensing substances are non-stoichiometric. The resulting solids have compositional disorder and complex macroscopic properties, such as giant susceptibilities and non-ergodicity. Here, we observe the spontaneous formation of a cubic structure in composite ferroelectric potassium-lithium-tantalate-niobate with micrometric lattice constant, 10(4) times larger than that of the underlying perovskite lattice. The 3D effect is observed in specifically designed samples in which the substitutional mixture varies periodically along one specific crystal axis. Laser propagation indicates a coherent polarization super-crystal that produces an optical X-ray diffractometry, an ordered mesoscopic state of matter with important implications for critical phenomena and applications in miniaturized 3D optical technologies.

中文翻译：

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复合铁电体中的超晶体。

随着原子和分子凝结形成固体，晶态会以其高度有序的几何形状和亚纳米晶格常数出现。在某些物理系统中，例如铁电钙钛矿，即使缩合物质不是化学计量的，也能形成理想的晶体结构。所得的固体具有组成紊乱和复杂的宏观性质，例如巨大的磁化率和非遍历性。在这里，我们观察到复合铁电钾-钽-铌酸盐-铌酸盐复合材料中立方结构的自发形成，其晶格常数比下面的钙钛矿晶格常数大10（4）倍。在专门设计的样品中观察到3D效果，其中替代混合物沿一个特定的晶体轴周期性变化。