Magnetism in the magnetoelectric hexaferrite system (Ba1-xSrx)(2)Zn2Fe12O22
2007 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 76, no 2, 024432- p.Article in journal (Refereed) Published
The hexaferrite system (Ba1-xSrx)(2)Zn2Fe12O22 possesses a rich magnetic phase diagram and for strontium content x=0.75 exhibits a magnetoelectricity, the existence of which is intimately connected to the noncollinear arrangement of the iron spins. The system comprises seven cation sublattices, two of which have tetrahedral coordination. The tetrahedral sublattices are partly occupied by Fe and partly by Zn. Using ab initio-calculated exchange interactions we show that the magnetism in the (Ba1-xSrx)(2)Zn2Fe12O22 system is sensitive to the Fe and Zn distributions. The region of existence of the noncollinear spin structure and hence of ferroelectricity is determined and found to be rather narrow. The critical temperature of magnetic ordering is calculated using molecular field and random phase approximations. The results are in good agreement with the experiment.
Place, publisher, year, edition, pages
2007. Vol. 76, no 2, 024432- p.
IdentifiersURN: urn:nbn:se:uu:diva-144059DOI: 10.1103/PhysRevB.76.024432ISI: 000248496200086OAI: oai:DiVA.org:uu-144059DiVA: diva2:392279