title: Thermally activated Peierls dimerization in ferromagnetic spin chains.
abstract: We demonstrate that a Peierls dimerization can occur in ferromagnetic spin chains activated by thermal fluctuations. The dimer order parameter and entanglement measures are studied as functions of the modulation of the magnetic exchange interaction and temperature, using a spin-wave theory and the density-matrix renormalization group. We discuss the case where a periodic modulation is caused by spin-phonon coupling and the case where electronic states effectively induce such a modulation. The importance of the latter for a number of transition metal oxides is highlighted.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany. j.sirker@fkf.mpg.de
authors.forename: Jesko
authors.initials: J
authors.lastname: Sirker
authors.forename: Alexander
authors.initials: A
authors.lastname: Herzog
authors.forename: Andrzej M
authors.initials: AM
authors.lastname: Oleś
authors.forename: Peter
authors.initials: P
authors.lastname: Horsch