Magnetism and superconductivity - Lefmann Group

We study the role of magnetism in materials. In particular, we are interested in the connection between the magnetism and the functionality of materials.

Examples of this area:
a) Unconventional superconductivity. We aim to understand the role of magnetism in the high-temperature superconductors, with the ambition to understand the origin of superconductivity in these elusive materials.

b) “Frustrated” magnets, where the  magnetic interactions cannot all be fulfilled simultaneously. This leads to a very shallow and complicated energy landscape, which in turn may lead to completely new states of matter.

c) Many-body quantum mechanical correlation (entanglement) in low-dimensional magnets. This leads to a number of exotic properties, such as fractional excitations.

The study takes place with a number of experimental and theoretical techniques, of which the most important is neutron scattering, soon to be undertaken at the new facility ESS that will open in Lund (S) in 2025. The theoretical efforts are often done in collaboration with the Condensed Matter Theory group (Kreisel, Andersen, Paaske). The group leads a national initiative, the "ESS Lighthouse" for Quantum Materials, Q-MAT, with the ambition to combine research efforts within magnetic and superconducting materials across the country.