Interdiffusion of polymers and water in colloids

Topic  37
Main supervisor M.Stekiel (m.stekiel@fz-juelich.de)
MLZ institution FZJ
Local supervisor 1 Karin Schmalzl
Institution ILL
Local supervisor 2 Alexander Regnat
Institution Kiutra GmbH
Local supervisor 3
Institution
Local supervisor 4
Institution
Title Understanding multiferroic properties of TbFeO3 by studying its magnetic excitations
Description Multiferroics have revolutionized the field of multipurpose materials with tunable physical properties. Owing to the coupling between the structural, magnetic, and electronic degrees of freedom, they are a class of materials where a property emerging from one of those degrees of freedom can be controlled by varying the other one by an external control parameter such as applied magnetic field, electric field or pressure.
At the same time, the exotic mechanisms of the interplay between those degrees of freedom in particular compounds became themselves a matter of study in condensed matter physics. In TbFeO3 the interplay of Tb and Fe magnetic sublattices creates magnetic phases with exotic properties. The phase diagram is well described, but the interactions originating the exotic behavior are not determined yet. By means of neutron and possibly x-ray spectroscopy we suggest to study he excitation spectra with and without magnetic field, and further to calculate the spin waves and coupling parameters.
As part of the project, there will be experiments performed on different international sources as well as on MLZ instruments including PANDA/BAMBUS, and contributing in improving the instrument or the analysis software are options to develop the own skills of the fellow. Cooperation is foreseen at least with ESS.