ALTEX explores the ultrafast physics of altermagnets—an emerging class of compensated magnets that combine vanishing macroscopic magnetization with a momentum-dependent spin splitting. The project forms part of the DFG Priority Programme SPP 2558: “Unconventional Magnetism: Beyond the S-Wave Magnetism Paradigm”.
Combining time- and angle-resolved photoemission with broadband magneto-optical spectroscopy, we will follow the evolution of electronic bands, magnons, phonons, excitons, and orbital transitions on femtosecond timescales. Starting with α-MnTe as a benchmark altermagnet, we will investigate how optical excitation modifies exchange-driven band splitting and how below-gap excitations couple electronic, spin, and lattice degrees of freedom.
Particular attention will be devoted to the optical generation of altermagnetic magnons and to excitation pathways arising specifically from altermagnetic symmetry. By extending these studies from bulk α-MnTe to novel two-dimensional and hybrid altermagnets developed within SPP 2558, ALTEX aims to establish the microscopic foundations for the ultrafast optical control of unconventional magnetism and future terahertz spin technologies.