2D Layered Materials




We explore fundamental optical and optoelectronic properties and novel functionalities of two dimensional layered ‘van der Waals’ materials such as semiconducting transition metal dichalcogenides, e.g. MoS2, topological insulators, e.g. Bi2Se3 and perovskite nanosheets. We experimentally study generated photocurrents in these atomically thin membranes with high spatially resolution. Phonons as well as collective charge and spin excitations are investigated by resonant inelastic light scattering experiments. The development of a highly versatile experimental test-platform facilitates measurements in vacuum, at low-temperatures, in water and ambient conditions. Our complementary approach provides the capability to gain deep insight into fundamental optoelectronic processed including charge carrier generation, separation and dynamics, their interaction with the solid state matrix and environment.


Recent Highlights 

Photogating of mono- and few-layer MoS2

Photocatalytic Stability of Single- and Few-Layer MoS2

Fractionally charged skyrmions, electronic excitations and optical emission in the fractional quantum Hall effect

Chemical potential fluctuations in topological insulator (Bi0.5Sb0.5)2Te3-films visualized by photocurrent spectroscopy

Resonant Inelastic Light Scattering Investigation of Low-Lying Gapped Excitations

Local photocurrent generation in thin films of the topological insulator Bi2Se 3

Micro-Raman spectroscopy of MoS2 under various conditions and on different substrates

Photocurrent measurements on MoS2-nanosystems

Resonant Intelastic Light Scattering on Mono- and Few-layer MoS2



Joel W. Ager (Berkeley, USA), Anna Cattani-Scholz (WSI-TUM), Aron Pinczuk (Columbia University, USA), Özge Sağlam (E20, TUM), Peter Thiessen (accurion GmbH)


Recent Publications

A list of recent publications can be found here.



Funding by the following institutions is gratefully acknowledged: 

DFG, Priority Program 1666: Topological Insulators


Dr.-Ing. Leonhard Lorenz Stiftung

TUM Technische Universität München TUM Technische Universität München Physik Department Elektrotechnik und Informationstechnik TUM Technische Universität München