Dresden 2026 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 59: 2D Materials V – Magnetic, spintronic, and topological properties (joint session HL/TT)
TT 59.6: Talk
Wednesday, March 11, 2026, 16:45–17:00, POT/0081
Probing spin-orbit coupling in graphene/WSe2 heterostructures by the circular photogalvanic effect — Ernst Knöckl, •Matthias Klein, Alexander Holleitner, and Christoph Kastl — Walter Schottky Institute, School of Natural Sciences, Technical University of Munich
We investigate proximity-induced spin–orbit coupling (SOC) in
graphene/WSe2 heterostructures using the circular photogalvanic
effect (CPGE) as a symmetry-selective and experimentally accessible
probe of spin–valley-locked band textures [1]. By measuring helicity-dependent photocurrents as a function of gate voltage, excitation
energy, and device geometry, we aim to disentangle Rashba and
valley-Zeeman SOC contributions and to extract their magnitude and sign
as a function of the graphene–WSe2 twist angle. The observed
trends in CPGE sign reversals and scaling behavior provide
quantitative indications of interfacial symmetry breaking and
moiré-enhanced spin–valley coupling, supported by comparison to
microscopic transport models. These results are expected to establish
CPGE as a promising metrological probe of proximity SOC in 2D
heterostructures and to complement ongoing efforts in
twist-angle-dependent spin–orbit engineering in graphene/TMD systems [2,3].
[1] Kiemle, J., et al. ACS nano 16.8, 12338-12344 (2022)
[2] Yang, H., et al. Nat. Mater. 23, 1502-1508 (2024)
[3] Zhang, Y., et al. Natur 641, 625-631 (2025)
Keywords: spin-orbit coupling; proximity effect; twist angle; photocurrent