Thanks to Prof. Matthieu Le Tacon, we are pleased to have Yi and Sebastian to our upcoming alumni event, where they will share their career insights and advice with KSQM members.

Yi Yao:  From Quantum materials to laser physics: a journey from KIT to industrial photonics at TRUMPF

Yi was born in Chengdu, China, and began her academic journey in Materials Science and Technology at the University of Science and Technology Beijing. Driven by a curiosity for advanced materials, she pursued a prestigious Erasmus Mundus double master’s degree, studying in France (University of Rennes 1) and Germany (LMU/TUM), graduating with distinction.

In 2018, Yi joined the Institute of Quantum Materials and Technology (IQMT) of Prof. Matthieu le Tacon at KIT as a research associate. Her doctoral research focused on light-matter interactions in quantum materials using advanced spectroscopic techniques, uncovering complex couplings and phase behaviors in correlated electron systems.

After defending her PhD in 2021, Yi transitioned into industry, joining TRUMPF as a system engineer. There, she worked on the development and integration of the driver laser—an essential light source in the EUV lithography process—supporting prototype testing, customer site acceptance, and system-level performance analysis. After two years, she moved to the simulation group, where she is currently focused on modeling and optimizing laser amplification processes. Her work allows her to apply and expand on her background in spectroscopy and laser technology while contributing to the interface between research and industrial development.

Sebastian: From Scientific Foundations to High-Tech Innovation

Sebastian grew up in a small village nestled in the Palatinate Forest before moving to Karlsruhe to study physics at KIT. During his Master's thesis at the Physical Institute, he investigated the electronic properties of the rare-earth element cerium—particularly at low temperatures—focusing on the crucial role played by its solitary 4f electron.

For his PhD, he joined the Institute for Quantum Materials and Technologies (IQMT) at KIT, where he explored frustrated quantum critical systems in heavy fermion compounds, again under extreme cryogenic conditions.

After completing his doctorate, transitioned into industry, joining the R&D department at Physik Instrumente (PI), a global leader in ultra-precise positioning technologies. Today, he works as a Senior Research Engineer in the Global Innovation unit, where his focus spans optics, simulations, and integrated photonics. Drawing on his academic experience, he also leads the company’s focus team on Vacuum and Cryogenics, and serves as an innovation scout for both photonics and cryogenic technologies.