Molecular beam epitaxy of antiferromagnetic (MnBi₂Te₄)(Bi₂Te₃) thin films on BaF₂ (111)

The layered van der Waals compounds (MnBi₂Te₄)(Bi₂Te₃) were recently established as the first intrinsic magnetic topological insulators. We report a study on the epitaxial growth of (MnBi₂Te₄)_m(Bi₂Te₃)_n films based on the co-deposition of MnTe and Bi₂Te₃ on BaF₂ (111) substrates. [...]

J. Appl. Phys. 128, 135303 (2020)

Incorporation of Europium in Bi₂Te₃ Topological Insulator Epitaxial Films

In the field of topological materials, the interaction between band topology and magnetism remains a current frontier for the advancement of new topological states and spintronic functionalities. Doping with rare-earth elements with large magnetic moments is a current approach to exploit the phenomenology of such interaction. However, dopant solubility into the main matrix plays a major role. [...]

J. Phys. Chem. C 2020, 124, 16048-16057

Electronic structure of epitaxial perovskite films in the two-dimensional limit: Role of the surface termination

An often-overlooked property of transition metal oxide thin films is their microscopic surface structure and its effect on the electronic properties in the ultrathin limit. Contrary to the expected conservation of the perovskite stacking order in the (001) direction, heteroepitaxially grown SrIrO₃ films on TiO₂-terminated SrTiO₃ are found to exhibit a terminating SrO surface layer. [...]

Appl. Phys. Lett. 116, 201601 (2020)

Nanophysics at surfaces

The research activities of our group are concerned with the physics of low-dimensional systems, where the electron states resulting from dimensional confinement lead to unusual conduction properties and to phase transitions as a function of temperature.

Oxide interfaces

Our group focusses on the electronic structure of correlated systems in transition metal oxides (TMOs). Special interest lies in the interplay of different degrees of freedom (charge, spin, orbital, lattice) in the light of metal-insulator and other phase transitions.

Neutron and resonant X-ray spectroscopy

In our group we investigate complex, functional materials such as transition metal oxides, which are used in the emerging field of correlated nanoelectronics. Unlike with conventional semiconductors, exotic superconducting, orbital and magnetic states can be realized at the interfaces in layered structures comprising such materials.