Special AEP Seminar: Mengjie Yu Ph.D. ’18 (USC)

Thin film lithium niobate: an emerging nanophotonic platform for nonlinear optics

Lithium niobate (LN) is an excellent nonlinear photonic material due to its large electro-optic (EO) coefficient, second order (χ2) and Kerr (χ(3)) nonlinearity, along with a wide optical transparency window. Thanks to the recent advances in nanofabrication technology, monolithic LN waveguides with high optical confinement and ultralow linear loss has been achieved, which was critical to the success of the silicon-based platform in the past decade. Highly efficient and controllable light-matter interactions can be achieved using optical, electrical, or mechanical waves at extremely compact footprints. In this talk, I will review our recent developments of 1) few cycle light generation via EO modulators 2) optomechanics based oscillators and its application for room temperature infrared detectors 3) optical frequency comb generation for optical computing and metrology. Combination of multiple nonlinearities of LN unlocks ultrabroadband electromagnetic spectrum from microwave to mid-infrared. Lastly, I will discuss the potential of LN photonic platform for scaling up and accelerating classical and quantum technologies in sensing and communication networks.

Bio:
Mengjie Yu is the Gabilan Assistant Professor in the Department of Electrical and Computer Engineering at the University of Southern California and will be an assistant professor of electrical engineering and computer science and a Weber Family Engineering Faculty Fellow at the University of California, Berkeley starting January 2025. She received her Ph.D. degree in electrical and computer engineering in 2018 from Cornell University and held research staff associate position in the Department of Applied Physics and Mathematics at Columbia University from 2015-2018. She was a postdoctoral fellow in the John A. Paulson School of Engineering and Applied Sciences at Harvard University from 2018-2021.

Her research group focuses on developing nanoscale nonlinear and quantum photonics devices for optical communication, computing, sensing, and metrology. She serves on the Early Career Editorial Advisory Board for APL Photonics. She is the 2020 the Optica (formerly OSA) Ambassador, the Caltech 2019 Young Investigator Lecturer and received DARPA Young Faculty Award at 2023 and Intel Rising Star Award at 2024.