Colloquium: Dr. Hui Deng | University of Michigan

ABSTRACT: Van der Waals materials have emerged as a revolutionary platform for photonics, offering a unique combination of direct-bandgap semiconductor properties and unprecedented flexibility for heterostructure integration. These materials exhibit simultaneously strong optical responses

and unusual physical properties that enable access to coherent light-matter interaction regimes previously considered inaccessible in traditional bulk materials.

In this talk, we will discuss a few examples, including the observation of collective Lamb shift 1 and achievement of perfect absorption 2 within a same monolayer, the development of unconventional types of strong- coupling systems with unique properties 3–5 , and an approach that utilizes some of the novel effects to enable a dynamic matter-light hybrid Chern insulator 6,7 . These advances open new pathways to next generation photonic devices and quantum technologies.

1. Horng, J. et al. Engineering radiative coupling of excitons in 2D semiconductors. Optica 6, 1443 (2019).

2. Horng, J. et al. Perfect Absorption by an Atomically Thin Crystal. Phys. Rev. Appl. 14, 024009 (2020).

3. Zhang, L., Gogna, R., Burg, W., Tutuc, E. & Deng, H. Photonic-crystal exciton-polaritons in monolayer semiconductors. Nat. Commun. 9, 713 (2018).

4. Zhang, L. et al. Van der Waals heterostructure polaritons with moiré-induced nonlinearity. Nature 591, 61–65 (2021).

5. Li, Q. et al. Two-Dimensional Magnetic Exciton Polariton with Strongly Coupled Atomic and Photonic Anisotropies. Phys. Rev. Lett. 133, 266901 (2024).

6. Zhou, L. et al. Cavity Floquet engineering. Nat. Commun. 15, 7782 (2024).

7. Xie, X., Sun, K. & Deng, H. Polariton Chern Bands in 2D Photonic Crystals beyond Dirac Cones. Phys. Rev. X 15, 021061 (2025).

Hui Deng is a Professor of Physics and Electrical Engineering at the University of Michigan, Ann Arbor. Her research centers on the creation, control, and application of single- and many-body quantum states in matter-light coupled systems, with an overarching goal of developing robust quantum systems for future technology. She received her BS in Modern Applied Physics from Tsinghua University, followed by an MS in Electrical Engineering and a PhD in Applied Physics from Stanford University. She is a recipient of the NSF Career Awards, AFOSR Young Investigator Awards, and the Humboldt Foundation Friedrich Wilhelm Bessel Research Award. She is a fellow of APS and Optica.