A Comprehensive Investigation\ninto the Mechanisms\nDictating the Movement of Liquid Crystal Polymer Flakes in Liquid\nCrystal Hosts

Integrating microscale liquid crystal polymer flakes\ninto host\nmaterials takes advantage of their compact shape and heightened responsiveness\nto electric fields, facilitating a range of switching capabilities\nand related applications, such as smart windows and E-paper displays.\nHowever, the complex physics controlling the movement of these flakes\nwithin liquid crystal hosts remains partly mysterious. This paper\naims to elucidate the underlying physics that governs the behavior\nof nematic liquid crystal polymer flakes within nematic liquid crystal\nhosts. The uniaxial flakes are introduced into nematic liquid crystal\nhosts, which have positive or negative dielectric anisotropies. They\nare then arranged in devices with various alignment layers: parallel,\nperpendicular, or twisted. We compare and analyze the rotation and\nrelaxation times of these flakes, observing their behaviors at specific\nmoments to identify the factors influencing their motions. Our research\npinpoints three primary factors that impact the movement of these\nflakes: anchoring, elastic, and interfacial polarization effects.\nMoreover, elastic and anchoring effects play more prominent roles\nand contribute earlier than the interface polarization effect in the\nliquid crystalline hosts upon the application of electric fields;\nflakes can relax back to their initial state with the help of the\nanchoring effect. This comprehensive understanding not only contributes\nto the fundamental study of flake dynamics but also paves the way\nfor enhanced performance and broader practical applications, particularly\nin photoelectric fields, such as fast-switching smart windows.