This August, the Aachen Graphene & 2D Materials Center has gained new valuable expertise with the arrival of Dr. Lutz Waldecker as senior researcher in the Stampfer Group (2nd Institute of Physics A).
Waldecker is an expert on exciton physics and ultrafast dynamics in solids, in particular two-dimensional (2D) semiconductors. On his background, he has a Ph.D. at the Fritz Haber Institute of the Max Planck Society in Berlin, under the supervision of Ralph Ernstorfer, and a post-doc at Stanford University, in the group of Tony Heinz, where he worked on the optical and electronic properties of 2D semiconductors.
Among Waldecker’s recent results is the demonstration that dielectric screening causes a rigid shift of the single particle bands of 2D semiconductors, with little changes of the electronic dispersion . This observation suggests a new, noninvasive way of inducing nanoscale functionality in 2D semiconductors by acting on the substrate dielectrics – an approach that Waldecker is planning to explore as part of his research in Aachen.
Waldecker’s position is funded by a Feodor-Lynen return fellowship of the Alexander von Humboldt Foundation. “It is great to see that the Aachen Graphene & 2D Materials Center is getting increasingly competitive in attracting top-class researchers”, says Prof. Christoph Stampfer, “I’m looking very much forward to working together with Lutz!”
 L. Waldecker, et al. “Rigid Band Shifts in Two-Dimensional Semiconductors through External Dielectric Screening”, Phys. Rev. Lett. 123, 206403 (2019).