Anomalous Coexistence of Ferroelectric Phases (P parallel to a and P parallel to c) in Orthorhombic Eu1-yYyMnO3 (y > 0.5) Crystals

作者：Akaki Mitsuru^*; Hitomi Masaaki; Ehara Mizuaki; Akahoshi Daisuke; Kuwahara Hideki

来源：Journal of the Physical Society of Japan, 2011, 80(9): 094706.

DOI：10.1143/JPSJ.80.094706

• multiferroic
• magnetoelectric property
• perovskite manganese oxide
• phase diagram

We have investigated the magnetic and dielectric properties of orthorhombic Eu1-yYyMnO3 (0 <= y <= 0: 6) single crystals without the presence of the 4f magnetic moments of the rare-earth ions. In y >= 0: 2, the magnetic-structure driven ferroelectricity is observed. The ferroelectric transition temperature is steeply reducing with increasing y. In y >= 0: 52, two ferroelectric phases (P parallel to a and P parallel to c) are coexistent at low temperatures. In these phases, ferroelectricity has different origin, which is evidenced by the distinctive poling-electric-field dependence of electric polarization. Namely, the electric polarization along the c-axis (P-c) is easily saturated by a poling electric field, therefore Pc is caused by the bc-spiral antiferromagnetic order. On the other hand, the electric polarization along the a-axis (P-a) is probably attributed to the collinear E-type antiferromagnetic order, because P-a is unsaturated even in a poling field of 10(6) V/m.

• 出版日期2011-9