NSF/DMR-BSF: Liquid Crystals as a Paradigm for Chirality and Topological Defects

NSF/DMR-BSF：液晶作为手性和拓扑缺陷的范例

• 批准号: 1901797
• 负责人: Charles Rosenblatt
• 金额: $ 49.69万
• 依托单位: Case Western Reserve University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1901797&HistoricalAwards=false
• 关键词: NSF; DMR; BSF; Liquid; Crystals

Nontechnical Abstract:Chirality is the inability of an object to coincide with its mirror image, where the left and right hands are perhaps the best-known example. A topological defect occurs when the system's inherent "character", scientifically called its "order parameter", cannot be described uniquely at a point, line, or surface. Both phenomena are pervasive throughout nature, often are coupled, and are fundamental to central questions in science and technology. A few examples include chirality in quantum optics, semiconductor diodes, and biomaterials - DNA is the best known; chirality transfer, i.e., how chirality can be induced in an otherwise non-chiral materials; and interactions of multiple topological defects. This project focuses on chirality and topological defects using liquid crystals as a paradigm. Because of the long length scales and novel optical properties of liquid crystals, many of the associated phenomena can be visualized and measured quantitatively. This permits a general understanding of chirality and topological defects that would not be possible by studying other materials.Technical Abstract:Owing to their large optical, electrical, and magnetic anisotropies, liquid crystals are an ideal test bed for a multitude of phenomena in condensed matter and beyond. The central theme of this work is to exploit liquid crystals to explore seminal issues of chirality and topological defects that can impact the broader scientific enterprise. The PI utilizes his nanoscale techniques to create and image controlled chirality and defects at surfaces - sometimes in combination. Projects include: chirality transfer in biologically-relevant chiral nanocapsules to achieve the Holy Grail, viz., a measure of the chiral induction length; the creation of chiral multipoles; chiral topological defects, induced biaxiality, and skyrmions; multistable "rewiring" of line defects; chiral self-assembled monolayers for nanophotonics and semiconductors; and highly complex oily and soapy streak liquid crystalline defects. The PI's team employs a battery of experimental tools, including optical microscopy, confocal fluorescence microscopy, optical nanotomography, atomic force microscopy, AFM nanolithography, and ellipsometry. Much of the work is performed in collaboration with chemist Prof. David Avnir and his colleagues at the Hebrew University of Jerusalem. By exploiting the PI's ability to create exquisitely tailored nano-scale chiral and topological defect easy axis patterns, and to image liquid crystal orientation down to x,y,z dimensions of 50 x 50 x 2 nm, this work is transforming our conceptions about - and methodology toward - chirality, defects, how the two can be coupled in anisotropic fluids, and broader issues in condensed matter. In particular, the PI's work is leading to the understanding, quantification, and exploitation of induced chirality in otherwise achiral materials, as well as a deeper knowledge of chiral and achiral topological defects, their manipulation, and potential applications in optics and electronics. The issues studied cut across multiple disciplines, as consequences of chirality and defects appear throughout biology, chemistry, physics, medicine, pharmacology, and materials science.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.

非技术摘要：手征是指物体不能与其镜像重合，左手和右手可能是最著名的例子。 当系统的固有“特征”（科学上称为“序参量”）不能在点、线或面上唯一描述时，拓扑缺陷就发生了。 这两种现象在自然界中普遍存在，往往是相互关联的，是科学和技术中心问题的基础。 一些例子包括量子光学、半导体二极管和生物材料中的手性- DNA是最著名的;手性转移，即，如何在其他非手性材料中诱导手性;以及多个拓扑缺陷的相互作用。 本计画以液晶为范例，著重于手性与拓扑缺陷。 由于液晶的长尺度和新颖的光学性质，许多相关的现象可以可视化和定量测量。 这使得一般的了解手性和拓扑缺陷，将不可能通过研究其他material.Technical摘要：由于其大的光学，电学和磁各向异性，液晶是一个理想的试验台，在凝聚态物质和超越的现象众多。这项工作的中心主题是利用液晶来探索手性和拓扑缺陷的开创性问题，这些问题可能会影响更广泛的科学事业。 PI利用他的纳米级技术来创建和图像控制手性和表面缺陷-有时是组合。 项目包括：生物相关手性纳米胶囊的手性转移，以实现圣杯，即，手性诱导长度的测量;手性多极的产生;手性拓扑缺陷、诱导双轴性和skyrmions;线缺陷的多稳态“重新布线”;用于纳米光子学和半导体的手性自组装单层;以及高度复杂的油性和sobrystrake液晶缺陷。 PI的团队采用了一系列实验工具，包括光学显微镜，共聚焦荧光显微镜，光学纳米断层扫描，原子力显微镜，AFM纳米光刻和椭圆偏振法。 大部分工作是与耶路撒冷希伯来大学的化学家大卫·阿夫尼尔教授及其同事合作完成的。 通过利用PI的能力来创建精致定制的纳米级手性和拓扑缺陷易轴图案，并将液晶取向成像到50 x 50 x 2 nm的x，y，z维度，这项工作正在改变我们的概念-和方法-手性，缺陷，两者如何在各向异性流体中耦合，以及凝聚态物质中更广泛的问题。 特别是，PI的工作导致了对非手性材料中诱导手性的理解、量化和利用，以及对手性和非手性拓扑缺陷、其操纵以及在光学和电子学中的潜在应用的更深入了解。 研究的问题跨越多个学科，因为手性和缺陷的后果出现在生物学，化学，物理学，医学，药理学和材料科学中。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

项目成果

Magnetic field-induced Freedericksz transition in a chiral liquid crystal

手性液晶中磁场诱导的 Freedericksz 跃迁

• DOI: 10.1063/5.0146506
• 发表时间: 2023
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: Missaoui, Amine;Susser, Adam L.;Aharoni, Hillel;Rosenblatt, Charles
• 通讯作者: Rosenblatt, Charles

Co-revolving topological defects in a nematic liquid crystal.

向列液晶中的共转拓扑缺陷。

• DOI: 10.1039/d1sm01124c
• 发表时间: 2021
• 期刊: Soft matter
• 影响因子: 3.4
• 作者: Adam L. Susser;S. Kralj;C. Rosenblatt
• 通讯作者: C. Rosenblatt

Spontaneous Anchoring-Mediated Topography of an Orientable Fluid

• DOI: 10.1103/physrevlett.126.057803
• 发表时间: 2021-02-04
• 期刊: PHYSICAL REVIEW LETTERS
• 影响因子: 8.6
• 作者: Ferris, Andrew J.;Rosenblatt, Charles;Atherton, Timothy J.
• 通讯作者: Atherton, Timothy J.

Transition from escaped to decomposed nematic defects, and vice versa

• DOI: 10.1039/d0sm00218f
• 发表时间: 2020-05-28
• 期刊: SOFT MATTER
• 影响因子: 3.4
• 作者: Susser，Adam L.;Harkai，Sasa;Rosenblatt，Charles
• 通讯作者: Rosenblatt，Charles

Manipulation of mechanically nanopatterned line defect assemblies in plane-parallel nematic liquid crystals

• DOI: 10.1080/21680396.2022.2042745
• 发表时间: 2022-02-26
• 期刊: LIQUID CRYSTALS REVIEWS
• 影响因子: 5.1
• 作者: Harkai, Sasa;Cordoyiannis, George;Kralj, Samo
• 通讯作者: Kralj, Samo