抄録
Magnetic and dielectric properties of the ruthenium double perovskites R2MRuO6 were studied (R=La, Pr and Nd, M=Mg, Co, Ni and Zn). For R=La, the materials with the magnetic M2+ ions (M=Co and Ni) showed magnetic ordering and large dielectric constants (~5000). On the other hand, for the non-magnetic M2+ ions (M=Mg and Zn), magnetic ordering was not observed. In addition, their dielectric constants were found to be small (~100-200). Together with the imaginary part and the tan delta component of the dielectric response, the large dielectric constants for M=Co and Ni may be related to a smooth response of polar regions. Brief discussion for related materials R2MRuO6 with R=Pr and Nd is also described.
