Mechanism of Lattice-Distortion-Induced Electric-Polarization Flop in the Multiferroic Perovskite Manganites
Abstract
We theoretically study a competition between two types of spin cycloids (ab-plane and bc-plane ones) in the multiferroic perovskite manganites, which is an origin of intriguing magnetoelectric phenomena in these compounds. Analysis of a microscopic model using the Monte-Carlo method reveals that their competition originates from a conflict between the single-ion anisotropy and the Dzyaloshinsky-Moriya interaction. It is demonstrated that the conflict can be controlled by tuning the second-neighbor spin exchanges through the GdFeO3-type distortion, which leads to a cycloidal-plane flop from ab to bc observed in the solid-solution systems like Eu1-xYxMnO3 and Gd1-xTbxMnO3 with increasing x.
- Publication:
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Journal of the Physical Society of Japan
- Pub Date:
- May 2009
- DOI:
- 10.1143/JPSJ.78.053704
- arXiv:
- arXiv:0811.4015
- Bibcode:
- 2009JPSJ...78e3704M
- Keywords:
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- Condensed Matter - Strongly Correlated Electrons;
- Condensed Matter - Materials Science
- E-Print:
- 5 pages, 5 figures. Recalculated results after correcting errors in the assignment of DM vectors. The conclusion is not affected