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.
