清華大學材料科學與工程研究院《材料科學論壇》學術報告

報告時間：2024年1月9日下午14:00

報告人：張智峰 副教授

報告地點：清華大學逸夫技術科學樓A205學術報告廳

邀請人：孫競博老師

Spin-orbital angular momentum microlasers by symmetry engineering

報告簡介：

The angular momentum, both spin and orbital (OAM), carried by vortex light beams holds great promise for forefront development of high-capacity multi-dimensional spin-OAM optical communication and quantum information technologies. While the newly developed integrated meta-surfaces could flexibly generate vortex beams in a compact fashion, active generation and dynamic control of spin-OAM laser emissions from compact microlasers, suitable for high-speed, high-density and low-energy optical communication and computing, remains challenging. In this talk, I will present our recent works on developing various spin-OAM microlasers through non-Hermitian symmetry engineering. We demonstrated the first OAM microlaser by engineering the complex index modulation at an exceptional point. Furthermore, by harnessing optically controlled non-Hermitian symmetry breaking, we demonstrated an on-chip integrated spin-OAM tunable vortex microlaser. Recently, we scaled up the design and achieved a hyper-dimensional spin-OAM microlaser emitting in a 4-dimensional Hilbert space. Beyond, based on super-symmetry theory, we realized a 2-dimensional microlaser array with enhanced laser emission in radiance and divergence. Our work provides a route for the development of the next generation of multi-dimensional high-capacity information system in both classical and quantum regimes.

報告人簡介：

Zhifeng Zhang has been a tenure-tracked Associate Professor in the College of Engineering and Applied Science at Nanjing University since September 2022. He received his Ph.D. in Electrical and Systems Engineering from University of Pennsylvania in 2020 and was subsequently a postdoc researcher in the Department of Materials Science and Engineering at Penn. Currently his research interests include integrated photonics, metamaterials and microlasers. He has authored and coauthored more than 10 peer-reviewed papers in journals including Science, Nature, Light: Science & Applications, Laser & Photonics Reviews and PRL. He received NSFC Excellent Young Scientist Fund (Overseas) in 2021.