Multiferroic properties of RFe0.5Co0.5O3 with R= Tm, Dy, Er, Tb and Ho

J. LOHR; F. POMIRO; R. E. CARBONIO; R. D. SÁNCHEZ

Bariloche

Workshop; Exploratory Workshop on Condensed Matter Physics with Max Planck Institutes; 2017

Centro Atómico Barioche

We present magnetic and electric properties results of five members of the RFe0.5Co0.5O3 family with R= Tm, Dy, Er, Tb and Ho. From x-ray and neutron diffraction techniques, we characterize the samples as orthorhombic (Pbnm). For all samples, the magnetization as a function of temperature data have been measured at different magnetic fields, between 5K and 800K and under FCC (Field cool cooling) and ZFC (zero field cooling) protocols. The FCC and ZFC curves show a shift between them below the characteristics temperatures, which depend of R (TN, from 220 K to 285 K). This shifting evidence a magnetic frustration, although the extrapolation from high temperature of the inverse of magnetic susceptibilities show principally antiferromagnetic correlations between the magnetic ions. The electrical conductivity of the samples can be described with a semiconductors behavior following a VRH model, which is generally observed in systems with disorder. The pyroelectric currents taken increasing temperature were measured after cooling the samples under a high electrical field of 3keV/cm2 from T>TN. From these data we obtain the electric polarization, and the sign, of the pyroelectric current and the polarization is the same that the sign of the high electric field cooling. The magnitude of saturation polarization moment is approximately 0.04 uC/cm2. Our experiments demonstrate that the RFe0.5Co0.5O3 perovskite is a multiferroic material.