权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Enhancing helicity-dependent optical interactions in inversion-asymmetric materials

增强反演不对称材料中螺旋度相关的光学相互作用

基本信息

批准号：
1905209
负责人：
Jennifer Dionne
金额：
$ 45万
依托单位：
Stanford 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 2022-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905209&HistoricalAwards=false
关键词：
Enhancing helicity dependent optical interactions

项目摘要

Nontechnical description: The human eye has evolved to perceive the intensity and color of light. However, polarization provides an additional data-rich channel for information - a property is beautifully embodied by mantis shrimp and scarab beetles, species which see circularly polarized light. Many inversion asymmetric materials - including chiral molecules and atomically-thin materials - also preferentially 'see' (that is, absorb) left- or-right circularly polarized light, but only weakly; in fact, the differential absorption of left and right circularly polarized light is nearly five orders of magnitude less than these materials' absorption of unpolarized light. This project enhances the optical absorption and emission of circularly-polarized light in molecular and monolayer materials through the design, synthesis, and characterization of new materials and nanostructures that control light-matter interactions. By increasing chiral light-matter interactions, the research increases the efficacy and reduces the unwanted side effects of pharmaceutical drugs; reduces the toxicity and environmental impact of herbicides and pesticides; and facilitates efficient quantum optoelectronic information processing. As part of the project, the Principal Investigator is engaging in outreach and mentoring with K-12 students and teachers, giving particular attention to underrepresented groups; developing new undergraduate and graduate curriculum; and implementing a national theatre production via a playwright residency.Technical description: Many inversion-asymmetric materials, including chiral molecules and certain van der Waals materials, exhibit a differential absorption of left and right circularly polarized light that is nearly five orders of magnitude less than their absorption of unpolarized light. Such weak differential absorption prohibits applications including single molecule circular dichroism spectroscopy, all-optical chiral resolution, and efficient valleytronic data encoding for quantum information. This project focuses on enhancing helicity-dependent optical absorption, emission, and carrier relaxation in molecules and monolayered materials. The approach is based on nanostructured materials known as metasurfaces, which, when placed in the near-field of a molecular or monolayer sample, precisely control the amplitude, phase, and polarization of light. Full-field electromagnetic simulations are used to design metasurfaces for strong chiral-optical absorption and emission. In parallel, high-quality factor dielectric metasurfaces are fabricated and a suite of optical and atomic force microscopies are developed to characterize how the metasurfaces enhance molecular and monolayer circular dichroism, photoluminescence, and enantioselective absorption. Finally, the metasurfaces are used to manipulate electron spin orientation and carrier dynamics in molecular and van der Waals materials with broken inversion symmetry. Conclusions drawn from the project are expected to find applicability in all-optical enantioselective sensing and separation as well as quantum optical information generation, transmission and storage.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.

非技术描述：人眼已经进化到能够感知光的强度和颜色。然而，偏振为信息提供了一个额外的数据丰富的渠道--螳螂虾和金龟子甲虫很好地体现了这一特性，这些物种看到的是圆偏振光。许多反转不对称材料--包括手性分子和原子薄材料--也优先‘看到’(即吸收)左或右圆偏振光，但只是微弱的；事实上，左、右圆偏振光的微分吸收比这些材料对非偏振光的吸收小近五个数量级。该项目通过设计、合成和表征控制光-物质相互作用的新材料和纳米结构，增强了圆偏振光在分子和单层材料中的光吸收和发射。通过增加手性光与物质的相互作用，该研究提高了药物的疗效，减少了药物的不良副作用，减少了除草剂和农药的毒性和对环境的影响，并促进了高效的量子光电信息处理。作为该项目的一部分，首席研究人员正在与K-12学生和教师进行外联和指导，特别关注代表性不足的群体；制定新的本科生和研究生课程；并通过剧作家驻地实施全国戏剧制作。技术描述：许多反转不对称材料，包括手性分子和某些范德华材料，对左右圆偏振光的微分吸收比它们对非偏振光的吸收少近五个数量级。这种微弱的微分吸收限制了单分子圆二色谱、全光学手性拆分和高效的量子信息电子数据编码等应用。该项目致力于增强分子和单层材料中依赖螺旋度的光吸收、发射和载流子弛豫。这种方法是基于被称为亚表面的纳米结构材料，当放置在分子或单层样品的近场时，可以精确地控制光的幅度、相位和偏振。利用全场电磁模拟方法设计了具有强手性光吸收和发射特性的准表面。同时，制作了高品质因子介电准表面，并发展了一套光学和原子力显微镜来表征介电准表面如何增强分子和单层圆二色、光致发光和对映体选择性吸收。最后，将亚表面用于操纵分子和范德华材料中的电子自旋取向和载流子动力学。从该项目得出的结论有望在全光对映体选择性传感和分离以及量子光学信息的产生、传输和存储方面找到适用性。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。