The results of our high magnetic field THz spectroscopy measurements on the multiferroic Ba2CoGe2O7 are highlighted by the European Magnetic Field Laboratory.
In the spin excitation spectrum we found several spin excitations beyond the two conventional magnon modes expected for such a two-sublattice antiferromagnet. A multiboson spin-wave theory developed by Dr. Karlo Penc and Dr. Judit Romhányi describes the additional unconventional spin-stretching modes.