1202.4799 (M. Pregelj et al.)

Alternating spin chains coupled by frustrated interactions in the
multiferroic FeTe2O5Br    [PDF]

M. Pregelj, H. O. Jeschke, H. Feldner, R. Valentí, A. Honecker, T. Saha-Dasgupta, H. Das, S. Yoshii, T. Morioka, H. Nojiri, H. Berger, A. Zorko, O. Zaharko, D. Arčon

Density functional theory calculations performed for the multiferroic
FeTe2O5Br reveal surprisingly strong super-superexchange pathways through
Fe-O-Te-O-Fe bridges, implying that the magnetic lattice must be treated as a
system of alternating Fe chains coupled by frustrated interactions. We find
firm support for this model in the magnetization and the antiferromagnetic
resonance measurements as well as in the matching of the incommensurate
magnetic vector. Its peculiar temperature dependence is explained by interchain
exchangestriction being responsible for the emergent net electric polarization.

View original: http://arxiv.org/abs/1202.4799