Regensburg 2019 – wissenschaftliches Programm
O 81.1: Hauptvortrag
Donnerstag, 4. April 2019, 10:30–11:00, H24
Zooming in on the electronic properties of van der Waals Heterostructures — •Søren Ulstrup1, Jyoti Katoch2, Roland J. Koch3, Simon Moser3, Kathleen M. McCreary4, Simranjeet Singh2, Jinsong Xu2, Berend T. Jonker3, Roland K. Kawakami2, Aaron Bostwick3, Eli Rotenberg3, and Chris Jozwiak3 — 1Department of Physics and Astronomy, Aarhus University, DK — 2Department of Physics, Ohio State University, USA — 3Advanced Light Source, Berkeley Lab, USA — 4Navel Research Lab, USA
Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) exhibit a diverse collection of intriguing electronic phenomena. These include single-particle effects related to new spin and valley physics, as well as exotic many-body interactions. The latter are exemplified by the presence of tunable band gaps and tightly bound excitons and trions. Here, I will show how the electronic properties of complex heterostructures composed of tungsten disulfide and boron nitride (WS2/hBN) can be accessed using angle-resolved photoemission spectroscopy with nano-scale spatial resolution (nanoARPES). I will present three major discoveries in such stacks: (i) The direct observation of the energy- and momentum-dependent electronic structure of one-dimensional TMD nanoscrolls, (ii) a substrate-induced lateral band bending, demonstrating ultimate control of band offsets at the nanoscale, and (iii) a doping dependent three-particle excitation in the measured spectral function which is consistent with the formation of a trion.