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Project: Computational and experimental studies of topological materials and their heterostructures with ferromagnets

So-called topological materials have unique physical properties. In this project, theoretical as well as experimental studies will be used to explore the possibilities offered by these materials.

Project information

Project manager
Janusz Sadowski
Other project members
Carlo Canali, Md Fhokrul Islam, Cecilia Holmqvist and Nezhat Pournaghavi, Linnaeus University
Participating organizations
Linnaeus University, MAX IV Synchrotron Laboratory in Lund, Uppsala University, Chalmers University of Technology; Sweden
Vetenskapsrådet (the Swedish Research Council)
1 Jan 2018-31 Dec 2021
Physics (Department of Physics and Electrical Engineering, Faculty of Technology

More about the project

Heterostructures, fabricated by molecular beam epitaxy technique, combining topological semimetals (TSMs) with ferromagnets (FMs) or antiferromagnets (AFMs), will be investigated.

TSMs are a novel family of topological materials recently experimentally realized which display remarkable transport properties. Due to time-reversal symmetry and strong spin-orbit effects, in topological materials the charge carriers are protected against back-scattering and locked with their spin. In STMs this topological protection is a bulk property, in contrast to topological insulators, where it is a property of the surface states only. The symmetry providing the topological protection in topological materials can be broken by time-reversal breaking perturbations. Thus heterostructures combining ferromagnetic layers with TSM materials will be studied.

Among possible TSMs, we will consider Ta and Nb pnictides, PtSn4 and Mn3Sn. The magnetic layer will comprise FMs such as (Ga,Mn)As diluted magnetic semiconductor, Mn pnictides and MnGa, or AFs such as CuMnAs. Magnetic perturbations will also be realized by doping the TSMs with Mn magnetic transition-metal ions. Doping with Sb and Bi heavy elements will be further investigated in order to modify the TSM properties by enhancing the spin-orbit coupling strength.

Extensive theoretical modeling based on quantum mechanical first-principles calculations will be provided. This project will uncover new phenomena relevant for spintronics.

The project is part of the research in the Condensed Matter Physics research group.

See also the press release for the project.