三维自组装蓝相液晶光子晶体

Three Dimensional Self-Assembled Blue Phase Liquid Crystalline Photonic Crystal

蓝相液晶由于其独特的三维自组装结构、可见光波段的选择性光反射性能和软物质特性,被认为是最具发展潜力的可调三维光子晶体材料之一,在下一代超快响应显示、反射型显示、可调激光器和光通信等领域具有广阔的应用前景。本文综述了近年来蓝相液晶自组装结构的研究进展,包括蓝相的多级自组装三维微纳结构及子相相变行为的最新研究,通过基板表面取向处理或纳米图案化诱导、电场诱导、热处理诱导等方法控制蓝相自组装行为和三维周期性晶体结构的研究现状,以及蓝相光子晶体材料在可调谐激光器、可调光栅等光学器件领域的应用研究,最后对该领域的目前存在的挑战和未来发展方向进行了展望。

Blue phase(BP)liquid crystals have been regarded as one kind of the most promising candidates for tunable three-dimensional photonic crystals due to their unique 3 D self-assembly nanostructures,photonic bandgaps in visible light range and characteristics of soft matter.They exhibit great potential in numerous applications such as next-generation ultra-fast displays,reflection-mode displays,tunable lasers and optical communication devices.Herein,we provide the research advancement in the self-assembly structures of blue phase liquid crystals in recent years.First,the latest research on the hierarchical self-assembly of three-dimensional micro/nano structural and phase transition behaviors between three sub-phases are introduced.Then,the control methods of their self-assembly behavior or three-dimensional periodic lattice structures are demonstrated in detail.The lattice nucleation growth and lattice orientation of BPI and BPII can be modulated by substrate surface orientation treatment or nano patterning treatment.Owing to the response characteristics of BPs to external electric field,monodomain cubic crystals of BP or new sub-phase with non-cubic nanostructure can be obtained by controlling applied electric field.Besides,BP photonic crystals with different plane orientations can be obtained in a short time by appropriate heat treatment.These studies provide theoretical foundation for the appreciable application of BP materials in three-dimensional photonic crystals and functional devices.For example,the applications of blue phase liquid crystalline photonic crystal materials in optical fields such as tunable laser and tunable grating are shown.At the end of this review,the challenges and possible development direction of blue phase liquid crystalline photonic crystal is prospected briefly.