Evidence of large magneto-dielectric effect coupled to a metamagnetic transition in Yb{sub 2}CoMnO{sub 6}

• Published in: Applied physics letters 2015-07, Vol.107 (1)
• Main Authors: Blasco, J., García, J., Stankiewicz, J., Subías, G., García-Muñoz, J. L., Ritter, C., Rodríguez-Velamazán, J. A., Institute Laue Langevin, BP 156, 38042 Grenoble Cedex 9
• Format: Article
• Language: English
• Subjects: ANTIFERROMAGNETISM; CAPACITANCE; CATIONS; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COBALT IONS; FERROELECTRIC MATERIALS; MAGNETIC FIELDS; MAGNETIZATION; MANGANESE IONS; NEUTRON DIFFRACTION; NEUTRONS; PERMITTIVITY; PEROVSKITE; PHASE TRANSFORMATIONS; POLARIZATION; POTASSIUM 40
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4926403

The double perovskite Yb{sub 2}CoMnO{sub 6} has been synthesized with an almost perfect checkerboard arrangement of Co{sup 2+} and Mn{sup 4+} cations in the B-sublattice of the perovskite cell. It presents an anomaly in the electric capacitance and a strong magneto-dielectric effect at about 40 K whose interplay with the microscopic magnetic behavior has been investigated by means of neutron diffraction, magnetization, pyroelectric, and relative dielectric permittivity measurements. We show that the onset of an E-type antiferromagnetic ordering of Co{sup 2+} and Mn{sup 4+} moments monitored by neutron diffraction provokes the noticeable jump of the relative dielectric permittivity (∼9%) at about 40 K. It is also shown that this jump can be totally suppressed by application of a magnetic field of μ{sub 0}H = 5 T. Neutron experiments and magnetic measurements confirm that such a suppression leading to a significant magneto-dielectric effect is driven by a metamagnetic phase transition from the peculiar E-type ordering of 3d moments into a collinear ferromagnetic order. Pyroelectric current measurements do not show any spontaneous electric polarization, so the large dielectric anomaly at zero field cannot be ascribed to a ferroelectric ordering.