Strongly-correlated electron system on pyrochlore-type oxides with metal-insulator transition

用固相法成功地合成了焦绿石型Ruthenate Pb2-xLnxRu2O7-(Ln=Y，ND)。Pb2-xLnxRu2O7-(Ln=Y，Nd)固溶体化合物随着x的增加经历了从金属态(x=0)到绝缘态(x=2)的转变。由于Ru位上的局域磁矩，x&gt；0.2的化合物在低温(T&lt；TSG)也表现出类似自旋玻璃的行为。电阻率测量结果表明，χ为0.4χ0.8的样品发生了金属-绝缘体转变。在金属区，电阻率值服从T2依赖关系，这表明该体系中的电子行为是强关联的。

The pyrochlore ruthenates Pb2-xLnxRu2O7- (Ln = Y, Nd) have been successfully synthesized by the solid-state reaction. The solid-solution compounds of Pb2-xLnxRu2O7- (Ln = Y, Nd) undergo a crossover from metallic (x = 0) to insulating (x = 2) with increasing x. Owing to a localized magnetic moment on Ru site, these compounds with x > 0.2 also indicate the spin-glass like behaviors at low temperature (T < TSG). As a result of electric resistivity measurements, the samples with 0.4 ? χ ? 0.8 show the metal-insulator transition. In the metallic region, values of electric resistivity obey T2 dependencies which indicate the strongly correlated electron behaviors in this system.