CAREER: Topology and Symmetry Enabled Phenomena in Lasers and Other Non-Hermitian Photonic Media

该职业奖支持一项综合研究、教育和推广项目，重点研究激光和其他光子介质中由拓扑和对称引起的新现象。拓扑和对称不仅在艺术和产品设计中发挥着重要作用，而且它们也是决定微观世界行为的基础。尽管这种效应在很大程度上是肉眼难以捉摸的，但使用普通的光学设备，比如比价格扫描仪复杂不了多少的激光，就可以识别出它们有趣特性的某些方面。这个项目的目标是在我们对能量产生和耗散的理解上取得重大突破，在光学和相关领域无处不在，影响由拓扑和对称控制的物理规则。这项研究的结果有望促进我们在光学和物理，以及材料科学和光电子学方面的基本认识。通过采用不同的范式来实现由拓扑和对称实现的新状态，光学和光子学可以提供超越自然界所提供的独特平台，并导致具有重要现实世界影响的技术创新。该项目的成功可能为新一代用于光通信和计算的复杂光子器件奠定基础，这将对我们的日常生活和整个社会产生深远的影响。该项目与国家光子学计划保持一致，该计划旨在将国家定位为下一代光子学技术的领导者；它也是研究人员研究所战略计划的一个组成部分，旨在促进光子学和其他变革领域的前沿研究。利用美国最大的城市大学系统纽约城市大学的资源，研究人员将与多个外展单位密切合作，以提高纽约市K-12学生对现代光学和光子学的认识和兴趣。该项目的跨学科性质将为研究生、本科生和高中生提供一个极好的研究机会，该研究将积极招募和指导学生，特别是来自STEM中代表性不足的群体的学生。该项目探索了物理学中两个最具活力的领域的新兴结合点，即物质的拓扑相和基于新型对称性的非厄米光子。在确定整数量子霍尔效应的拓扑起源的成功基础上，拓扑绝缘体的预测和观测引起了极大的兴奋，使物质拓扑相的研究成为现代物理学的焦点。同时，利用宇称-时间对称将量子力学扩展到非厄米体系，以及随后在光子学中的实现，导致了探索非厄米光子中自发对称性破缺及其带来的反直觉现象的活动的爆发。尽管将这两个令人兴奋的领域结合在一起有很有希望的发现，但仍不清楚非厄米系统的复值带结构如何与其边缘状态相关，以及后者在多大程度上受到拓扑和对称性的保护。本项目将通过以下三个目标来解决这些重要的和其他相关的问题：研究非厄米光子介质中不寻常的拓扑边缘态，重点研究它们的奇异局域性和一种新型的非厄米狄拉克点和Weyl点；研究一种新的称为复镜像对称的非厄米对称及其对高阶非厄米简并的影响；并利用半经典光学和量子光学工具探索对称保护光子零模激光器的特性。由于光学增益和损耗的灵活控制，可以在非厄米介质中实现光学和光子学中构建物质拓扑相的不同范式，这不仅丰富了基础光学物理，而且还导致了前所未有的具有独特光学功能的光子器件。物理部和材料研究部为该奖项提供资金。该奖项反映了美国国家科学基金会的法定使命，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。

This CAREER award supports an integrated research, education, and outreach project that focuses on the study of novel phenomena enabled by topology and symmetry in lasers and other photonic media. Topology and symmetry not only play an important role in arts and product designs, but they are also fundamental in determining the behaviors of the microscopic world. Even though such effects are largely elusive to the naked eye, certain aspects of their intriguing properties can be discerned using common optical devices, such as a laser not much more complicated than a price scanner. This project targets a major breakthrough in our understanding of how energy generation and dissipation, ubiquitous in optics and related fields, impact the physical rules governed by topology and symmetry. The outcome of this investigation is expected to advance our fundamental understanding in optics and physics, as well as in materials science and optoelectronics. By employing different paradigms to realize novel states enabled by topology and symmetry, optics and photonics can provide unique platforms beyond what nature has to offer and lead to technology innovations that have vital, real-world consequences. The success of the project may underpin a new generation of sophisticated photonic devices for optical communications and computing, which have far-reaching impacts on our daily lives and the whole society. This project aligns with the National Photonics Initiative, which aims at positioning the nation as a leader in next-generation photonics technologies; it is also an integral part of the strategic plan at the researcher's institute to promote cutting-edge research in photonics and other transformative areas. Leveraging the resources from the City University of New York, the largest urban university system in the US, the researcher will work closely with multiple outreach units to increase the awareness and interest of K-12 students in modern optics and photonics across New York City. The interdisciplinary nature of this project will provide an excellent research opportunity for graduate, undergraduate, and advanced high-school students, and the research will actively recruit and mentor students especially from underrepresented groups in STEM.This project explores the emerging juncture of two of the most energized fields in physics, namely topological phases of matter and non-Hermitian photonics based on novel symmetries. Built on the success of identifying the topological origin of the integer quantum Hall effect, the prediction and observation of topological insulators have created great excitement and put the study of topological phases of matter in the spotlight of modern physics. At the same time, the extension of quantum mechanics into the non-Hermitian regime using parity-time symmetry and its subsequent realization in photonics have led to an explosion of activities, exploring spontaneous symmetry breaking in non-Hermitian photonics and the counterintuitive phenomena they bring. Although there are promising findings combining these two exciting fields, it remains unclear how the complex-valued band structure of a non-Hermitian system is related to its edge states and to what extent the latter are protected by topology and symmetry. This project will tackle these important and other related questions through the following three aims: to investigate unusual topological edge states in non-Hermitian photonic media, focusing on their exotic localization properties and a new type of non-Hermitian Dirac and Weyl points; to examine a novel non-Hermitian symmetry termed complex mirror symmetry and its implication on high-order non-Hermitian degeneracies; and to probe the properties of symmetry-protected photonic zero-mode lasers using both semiclassical and quantum optical tools. Thanks to the flexible control of optical gain and loss, different paradigms towards building topological phases of matter in optics and photonics can be realized in non-Hermitian media, which not only enrich fundamental optical physics but also lead to unprecedented photonic devices with unique optical functionalities.The Physics Division and The Division of Materials Research contribute funds to this award.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.