Evaluation of the intrinsic magneto-dielectric coupling in LaMn0.5Co0.5O3 single crystals

The magneto-dielectric coupling in (l00) oriented LaMn0.5Co0.5O3 single crystals has been investigated using temperature, frequency, and magnetic field dependent dielectric response. Electronic transport data divulges that polaronic hopping arises due to Emin-Holstein adiabatic small polarons. Spin realignment through external magnetic field favors faster polaronic hopping by lowering activation energy for dielectric relaxation. Finally, positive magneto-dielectricity and magnetoloss under increasing magnetic field at high frequency of the exciting ac field confirms intrinsic magneto-dielectric effect in disordered ferromagnetic-insulator LaMn0.5Co0.5O3. This study also emphasizes the need to use single crystals as well as the frequencies higher than the corresponding inverse relaxation time. (C) 2014 AIP Publishing LLC.