We discovered a reversible electric polarization flop from the a axis (Pa) to the b axis (Pb) in multiferroic TmMn2O5 below 5K by applying a magnetic field of approximately 0.5T along the c axis. This phenomenon is the first example of the rare-earth (R) compound RMn2O5. This magnetic-field-induced polarization flop corresponds to a magnetic phase transition from one incommensurate magnetic (ICM) Pa phase to another ICM Pb phase, which is equivalent to an ICM Pb phase above 5K under no magnetic field. The spin chirality in the bc plane, which was observed in the Pb phase by polarized neutron diffraction, disappeared in the ICM Pa phase. This indicates that the polarization in the ICM phases of TmMn2O5 was induced by an Si×Sj-type interaction.
ASJC Scopus subject areas
- Physics and Astronomy(all)