Natural self-assembled three-dimensional photonic crystals such as blue-phase liquid crystals typically assume cubic lattice structures. Nonetheless, blue-phase liquid crystals with distinct crystal symmetries and thus band structures will be advantageous for optical applications. Here we use repetitive electrical pulses to reconfigure blue-phase liquid crystals into stable orthorhombic and tetragonal lattices. This approach, termed repetitively applied field, allows the system to relax between each pulse, gradually transforming the initial cubic lattice into various intermediate metastable states until a stable non-cubic crystal is achieved. We show that this technique is suitable for engineering non-cubic lattices with tailored photonic bandgaps, associated dispersion and band structure across the entire visible spectrum in blue-phase liquid crystals with distinct composition and initial crystal orientation. These field-free blue-phase liquid crystals exhibit large electro-optic responses and can be polymer-stabilized to have a wide operating temperature range and submillisecond response speed, which are promising properties for information display, electro-optics, nonlinear optics, microlasers and biosensing applications.

中文翻译：

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通过电致伸缩重构三维液晶光子晶体。

天然自组装三维光子晶体如蓝相液晶通常呈现立方晶格结构。尽管如此，具有不同晶体对称性和能带结构的蓝相液晶将有利于光学应用。在这里，我们使用重复的电脉冲将蓝相液晶重新配置为稳定的正交和四方晶格。这种称为重复施加场的方法允许系统在每个脉冲之间松弛，逐渐将初始立方晶格转变为各种中间亚稳态，直到获得稳定的非立方晶体。我们表明该技术适用于设计具有定制光子带隙的非立方晶格，蓝相液晶中整个可见光谱的相关色散和带结构，具有不同的成分和初始晶体取向。这些无场蓝相液晶表现出大的电光响应，并且可以被聚合物稳定以具有较宽的工作温度范围和亚毫秒级响应速度，这些特性在信息显示、电光、非线性光学、微激光器和生物传感应用。