Zografopoulos Dimitrios C, Beccherelli Romeo, Kriezis Emmanouil E
Consiglio Nazionale delle Ricerche, Istituto per la Microelettronica e Microsistemi, Via del Fosso del Cavaliere 100, 00133 Rome, Italy.
Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Oct;90(4):042503. doi: 10.1103/PhysRevE.90.042503. Epub 2014 Oct 17.
The tunable optical diffractive properties of zenithal bistable nematic liquid-crystal gratings are theoretically investigated. The liquid-crystal orientation is rigorously solved via a tensorial formulation of the Landau-de Gennes theory and the optical transmission properties of the gratings are investigated via full-wave finite-element frequency-domain simulations. It is demonstrated that by proper design the two stable states of the grating can provide nondiffracting and diffracting operation, the latter with equal power splitting among different diffraction orders. An electro-optic switching mechanism, based on dual-frequency nematic materials, and its temporal dynamics are further discussed. Such gratings provide a solution towards tunable beam-steering and beam-splitting components with extremely low power consumption.
从理论上研究了顶向双稳态向列型液晶光栅的可调谐光学衍射特性。通过Landau-de Gennes理论的张量公式严格求解液晶取向，并通过全波有限元频域模拟研究光栅的光传输特性。结果表明，通过适当设计，光栅的两个稳定状态可提供非衍射和衍射操作，后者在不同衍射级之间具有相等的功率分配。进一步讨论了基于双频向列型材料的电光切换机制及其时间动态。这种光栅为实现极低功耗的可调谐光束转向和光束分裂组件提供了一种解决方案。
