Electro-optical phase retarders based on newly discovered nematics

职务名称：基于新发现的液晶的电光器件液晶由相互平行排列的棒状分子组成。当放置在两个提供电场的透明电极之间时，分子重新排列，改变设备的光学对比度。 这些设备带来了平板电视、电脑显示器和智能手机行业的革命。 常规液晶的有害性质是它们对电场的极性不敏感，这导致相对大的操作电压和长的切换时间（毫秒）。该项目的重点是开发新的液晶器件，其中分子显示出对电场的极性响应。 目标是实现由弱电场驱动的快速（微秒和更快）光学响应。如果成功，该研究将满足新技术的需求，如人工智能，光交换，增强和虚拟现实以及深度学习，这些技术需要具有快速微秒和纳秒响应的电光设备。实验和理论分析的结合将提供一个极好的机会，教育学生在先进的电光技术。该建议是开发电光相位延迟器的基础上，新发现的液晶，如扭曲弯曲和铁电向列相，显示极性有序和极性响应的电场。其目标是在低于传统的电光延迟器的工作电压下实现超快的纳秒和微秒电光响应。该活动将集中在设备的基板的设计，赋予分子的适当对齐，然后使用电场来修改它们的取向和电极性，这将产生可辨别的光学响应。 研究将建立延迟器的最佳结构，由取向材料、基态有序化类型、电场的空间分布以及与电场的耦合机制来定义。包含新发现的向列相的器件的电光行为是复杂的，因为场响应的多个途径，例如体和表面极化、介电各向异性、离子输运、挠曲电性和与各向异性粘度、弹性和各向异性表面相互作用重叠的有序电性。该项目将产生极性和空间调制的分子排列如何产生电光响应的理解。变革性的价值在于具有快速响应的电可调谐和可切换光学相位延迟器的新设计概念的潜力。实验和理论分析的结合将提供一个极好的机会，教育学生在先进的电光技术。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

Title: Electro-optical devices based on newly discovered liquid crystalsLiquid crystals are composed of rod-like molecules that are aligned parallel to each other. When placed between two transparent electrodes that supply an electric field, the molecules realign, changing the optical contrast of the device. These devices brought a revolution in the industry of flat-panel TVs, computer monitors, and smartphones. A detrimental property of conventional liquid crystals is that they are not sensitive to the polarity of the electric field, which results in relatively large operating voltages and long switching times (milliseconds). The project focuses on developing new liquid crystal devices in which the molecules show a polar response to the electric field. The goal is to achieve fast (microsecond and faster) optical response driven by weak electric fields. If successful, the research will fulfill the demands of new technologies, such as artificial intelligence, optical switching, augmented and virtual reality, and deep learning, which require electro-optical devices with a fast microsecond and nanosecond response. A combination of experiments and theoretical analysis will provide a superb opportunity to educate students in advanced electro-optical technologies. The proposal is to develop electro-optical phase retarders based on the newly discovered liquid crystals such as twist-bend and ferroelectric nematics, which show polar ordering and polar response to an electric field. The goal is to achieve ultrafast nano-and microsecond electro-optic response at operating voltages lower than those used in conventional nematic retarders. The activity will focus on the design of the device’s substrate to impart a proper alignment of the molecules and then use the electric field to modify their orientation and electric polarity, which would generate a discernable optical response. The research will establish the optimum architecture of retarders, defined by the alignment materials, type of ground-state nematic ordering, the spatial distribution of the electric field, and coupling mechanisms to the electric field. The electro-optic behavior of devices containing the newly discovered nematics is complex because of multiple pathways of field response, such as bulk and surface polarization, dielectric anisotropy, ionic transport, flexoelectricity, and order electricity overlapped with anisotropic viscosity, elasticity, and anisotropic surface interactions. The project will yield an understanding of how the polar and spatially-modulated molecular arrangements produce an electro-optical response. The transformative value is in the potential for new design concepts of electrically tunable and switchable optical phase retarders with fast response. A combination of experiments and theoretical analysis will provide a superb opportunity to educate students in advanced electro-optical technologies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.