材料期刊网

本文采用固相反应法制备了BaxSr1-xRuO3和BaxSr1-xRu0．9Cr0．1O3两组样品，对比研究了它们磁性和电输运性质．当掺杂量少于0．2时，体系处于有少许畸变的钙钛矿的3C结构，Cr的掺人很大幅度提高了体系的铁磁转变温度L，电输运性质上也由坏金属行为转变为Mott绝缘体的行为，并且在铁磁相变附近出现电阻拐点．当掺杂量大于等于0．2时，体系发生结构相变，由畸变钙钛矿3c结构变为6M的单斜结构．这时，Cr的掺入对体系的影响并不明显．这些结果表明引起SrRuCh铁磁转变温度升高的Ru＋5-O-Cr＋3相互作用对晶格结构有强烈的依赖关系．

We prepared two series of compounds BaxSr1-xRuO3 and Bax Srl-x Ru0. 9 Cr0.1 03 by the solid state reaction method and compared their magnetic and transport properties. When x〈0. 2, the polycrystalline structure is regarded as a three-layered （3C） perovskite structure with a distortion. The Cr-doping can greatly improve the ferromagnetic transition temperature Tc, and the transport properties change from the Mott insulator into the bad metal and a turning point in resistance appears at the Curie temperature. For samples x〉-0. 2, a phase transition is ob- served. The system become a six-layered monoclinic （6M） structure and the Cr-doping will not significantly affect the properties of the system. These resultsshow that Ru＋5-O-Cr＋3 interaction, which is the major cause for the increase of Tc in Cr-doping in SrRuO3, strongly depend upon the lattice structure of the system.