Structural & Electronic Surface Dynamics
Research Group Ralph Ernstorfer, ERC project FLATLAND
Structural & Electronic Surface Dynamics
Research Group Ralph Ernstorfer, ERC project FLATLAND
Structural & Electronic Surface Dynamics
Research Group Ralph Ernstorfer, ERC project FLATLAND

News Post
New paper: Ultrafast modulation of a material's Fermi surface topology
Apr 2021

The transport of electrons is governed by the shape of the Fermi surface. We found that the topology of the Fermi surface of a semimetal can be manipulated on ultrafast timescales through optical excitation. A change in the Fermi surface topology, also called Lifshitz transition, can lead to the emergence of fascinating phenomena like colossal magnetoresistance and superconductivity. Combining time-resolved multidimensional photoemission spectroscopy and TDDFT+U simulations, we introduce a scheme for driving an ultrafast Lifshitz transition in the correlated type-II Weyl semimetal Td-MoTe2. We show that this non-equilibrium topological transition finds its microscopic origin in the dynamical modification of the electronic correlations.

Beaulieu et al., Science Advances 7, eabd9275 (2021). Link to press release.