CAREER: Chiral Phenomena of Excited States in Spintronics

非技术摘要：手性是自然界中普遍存在的现象，范围从基本粒子到化学和生物分子。大多数研究手征现象依赖于手征性的静态观点，即物体是否可以叠加在其镜像上。事实上，手性的概念可以扩展到移动的物体：例如，响尾蛇是一个旋转的陀螺，只在一个首选的方向旋转。在凝聚态系统中，动态手征性可以导致各种有趣的现象和应用。在这里，研究团队专注于原子级薄货车德瓦尔斯材料中结构，电子，磁动力学之间的手性相互作用。该研究项目汇集了先进的光谱学和建模技术，以研究手性相互作用产生的光学和传输特性。这些特性有望产生圆偏振光并实现电子的单向动力学，这可以实现新型光电器件应用。 该职业计划的研究方面与广泛的教育和推广活动机会相结合。研究生和本科生不仅在主要研究者的实验室接受材料科学，纳米纤维和激光物理学的培训，而且还使用国家实验室设施参与光谱实验。此外，研究团队积极参与K-12学生和公众通过开发新的STEM演示和游戏来传达手性的概念和对称之美。技术摘要：在凝聚态系统中，动态手性的概念扩展了自旋电子学的范围，具有各种有趣的特性。在这个过程中，手征性在不同自由度之间的能量和角动量传递中起着关键的作用。本计画的目的是研究二维材料与货车德瓦耳斯异质结构中，磁性、声子与光子激发间的手征相互作用所产生的新颖磁光效应与非互易输运性质。该研究小组正在寻求解决自旋电子学中几个最新和最相关的科学问题：1）如何相干激发手征声子并提升非手性材料中的手征声子简并？2)在二维极限下，手征性如何介导磁振子-声子耦合？以及3）如何在声子二极管器件中实现手性相互作用以实现非互易信号操作？一组国家的最先进的实验技术，如非线性光学，螺旋分辨拉曼散射，和铁磁共振光谱在国内机构和国家实验室进行的研究任务。本研究计划由材料研究部凝聚态物理计划（CMP）及促进竞争研究计划（EPSCoR）共同资助，旨在揭示更广泛材料中的手征现象，并推动自旋电子学与量子信息科学的跨学科发展该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical Abstract: Chirality is a ubiquitous phenomenon in nature, ranging from elementary particles to chemistry and biomolecules. Most studied chiral phenomena rely on a static view of chirality, that is, whether an object can be superimposed on its mirror image. In fact, the concept of chirality can be extended to moving objects: rattleback, for example, is a spinning top that only rotates in a preferred direction. In condensed matter systems, dynamic chirality can lead to a variety of interesting phenomena and applications. Here, the research team focuses on the chiral interactions between structural, electronic, magnetic dynamics in atomically thin van der Waals materials. The research project brings together advanced spectroscopy and modeling techniques to investigate the optical and transport properties emerged from chiral interactions. These properties hold the promise of producing circularly polarized light and realizing unidirectional dynamics of electrons, which can be implemented into novel opto-electronic device applications. The research aspects of this CAREER plan are integrated with extensive opportunities for education and outreach activities. Graduate and undergraduate students are not only trained in materials science, nanofabrication, and laser physics in the principal investigator’s lab, but also involved in spectroscopy experiments using national lab facilities. Also, the research team actively engage the K-12 students and general public to convey the concept of chirality and the beauty of symmetry by developing new STEM demos and games. Technical Abstract: In condensed matter systems, the concept of dynamic chirality expands the scope of spintronics with various intriguing properties. In this process, chirality plays a critical role in the energy and angular momentum transfer among different degrees of freedom. The objective of this project is to study novel magneto-optical effects and nonreciprocal transport properties that emerge from chiral interactions between magnetic, phononic, and photonic excitations in two-dimensional materials and van der Waals heterostructures. The research team are seeking to address several most current and relevant scientific problems in spintronics: 1) How to coherently excite chiral phonons and lift chiral phonon degeneracy in an achiral material? 2) How does chirality mediate the magnon-phonon coupling in the two-dimensional limit? and 3) How to implement chiral interactions in a phonon diode device for nonreciprocal signal operation? A battery of state-of-the-art experimental techniques at the home institution and the national laboratories such as nonlinear optics, helicity-resolved Raman scattering, and ferromagnetic resonance spectroscopy are employed to carry out the research tasks. This research project shed light on the emergent chiral phenomena in a broader class of materials and advance spintronics towards the interdisciplinary regime with quantum information science.This project is jointly funded by the Condensed Matter Physics Program (CMP) in the Division of Materials Research and by the Established Program to Stimulate Competitive Research (EPSCoR).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.