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An orthorhombic DyMnO 3 single crystal has been studied in magnetic fields up to 14 T and between 3 Kand room temperature. The field dependent ordering temperature of Dy moments is deduced. Theparamagnetic Curie Weiss behavior is related mainly to the Dy 3þ sublattice whereas the Mn sublatticecontribution plays a secondary role. DC magnetization measurements show marked anisotropicfeatures, related to the anisotropic structure of a cubic system stretched along a body diagonal, witha magnetic easy axis parallel to the crystallographic b axis. A temperature and field dependent spin floptransition is observed below 9 K, when relatively weak magnetocrystalline anisotropy is overcome bymagnetic fields up to 1.6 T.& 2013 Elsevier B.V. All rights reserved. 1. IntroductionManganites are manganese compounds of composition AMnO 3 ,where e.g. A¼ La, Ca, Ba,y, which crystallize in the cubic structureof the so called ‘‘perovskite mineral’’ CaTiO 3 . Depending on thecomposition they show a wide variety of magnetic and electricphenomena, including ferromagnetic, antiferromagnetic, chargeand orbital ordering. The multiferroic behavior and magnetoresis-tive effects make such oxides as natural candidates for potentialspintronics applications [1,2]. Intrinsic anisotropy is induced if theA site is occupied by different types of ions, with e.g. differentintrinsic charges. When the site A is partially or fully occupied by amagnetic ion, a severe intrinsic anistropy may be induced and thecompounds show different anisotropic behaviors as the tempera-ture is changed. This is considerable if the A ion has an f-shell, likein the rare earth ions. It is easily guessed that such anisotropicfeatures will surely depend on the orientation of any appliedmagnetic field.The perovskites manganites where A is a rare-earth (RE)element present the coexistence of magnetism and ferroelectricity.Moreover, either orthorhombic or hexagonal REMnO

Magnetic and electrical properties of electron-doped manganites Ca0.88Ce0.12MnO3 and Ca0.90Ce0.10MnO3 were studied in pulsed magnetic fields up to 60 T in the temperature range T = 1.5–260 K. Metamagnetic transition caused by the melting of the charge/orbital ordering and martensitic structural transition in a magnetic field was revealed. The transition is accompanied by a change in electrical resistivity of the sample by three orders. A magnetic phase diagram in the plane of the H–T was constructed. Higher values of the critical transition fields for the system Ca1−xCexMnO3, compared to the known system Ca1−xSmxMnO3 are explained by a narrower range of phase separation and a bigger difference between the Neel temperatures of the C and G-type antiferromagnetic phases, which originated from the difference between the valence of the Ce4+ and Sm3+ ions.

We report on Hall effect, longitudinal resistivity and magnetization measurements in the rutheno-cuprate RuSr 2 GdCu 2 O 8 . Combining these results we separate the anomalous contribution to the Hall effect and argue that the occurrence of canting and chirality have to be considered for describing this property.

We have made systematic measurements of the anomalous Hall effect in a PdFe and AuFe alloys. The Hall coefficient Rh has been measured as a function of applied magnetic field and temperature. The experimental results demonstrate that it is necessary to consider a negative contribution in addition to the canonical Karplus–Luttinger term. This difference term can be identified to the theoretically predicted chiral or real space Berry phase term and can be understood in terms of the Aharonov–Bohm-like intrinsic microscopic current loops arising from successive scatterings by canted local spins.