Abstract Details - Elisabeth Bothschafter

Ultrafast sublattice demagnetization dynamics of multiferroic TbMnO3
Presenter Elisabeth Bothschafter
Presentation Type Poster
Full Author List

E. Bothschafter, T. Kubacka, L. Rettig, E. Abreu, S. Manz, J. Saari, S.M.Koohpayeh, Y. Liu, F. Maccherozzi, S.S. Dhesi, M. Fiebig, S.L. Johnson, U. Staub

Affiliations

Paul Scherrer Institut

Abstract

We present the investigation of demagnetization dynamics in the multiferroic compound TbMnO3 in a picosecond optical pump- x-ray probe experiment. TbMnO3 becomes magnetically ordered at 42 K in a collinear spin-density-wave (SDW) sinusoidal phase with a temperature dependent magnetic propagation vector.

Below 27K the structure forms a rigid non-collinear spin-cycloidal phase with spontaneous electric polarization. The propagation vector of the magnetic order gives rise to magnetic reflections (0 q 0) in resonant X-ray diffraction at the Mn LII edge. We seek to establish how and at which timescales the magnetic order transforms upon photoexcitation, and to determine whether direct switching from the cycloidal phase to the magnetically disordered state is possible.

To this end we compare the time-resolved demagnetization dynamics starting from the multiferroic and from the SDW phase in both sigma and pi polarization of the X-ray probe. Our results show that the demagnetization from the multiferroic phase happens via a transient SDW phase and that the demagnetization slows down in the high temperature phase.