title: Zener polaron ordering variants induced by A-site ordering in half-doped manganites.
abstract: We have studied the magnetism of the half-doped charge ordered manganite YBaMn2O6. A formation of ferromagnetic plaquettes of four Mn atoms in the charge ordered phase below T_{CO} approximately 480 K is inferred from high temperature magnetic susceptibility data and the magnetic structure, as determined by neutron powder diffraction at T=1.5 K. The results indicate that new fourfold Mn paramagnetic units form between T_{N}<T<T_{CO}, and that they order in a noncollinear mode below T_{N}=190 K. The magnetism of YBaMn2O6 is consistent with what is expected from the Zener polarons ordering picture of the charge ordering phenomenon in manganites [A. Daoud-Aladine, Phys. Rev. Lett. 89, 097205 (2002)10.1103/PhysRevLett.89.097205].
authors.affiliation: ISIS Facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Daoud-Aladine
authors.forename: C
authors.initials: C
authors.lastname: Perca
authors.forename: L
authors.initials: L
authors.lastname: Pinsard-Gaudart
authors.forename: J
authors.initials: J
authors.lastname: Rodríguez-Carvajal