Superconductivity and structure analysis of Ru-based Sr2YRuO6 2116 Cu-doping system

• Main Authors: Chen, Dinyeuan, 陳定遠
• Other Authors: F.Z.Chien
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/33955535184236021881

博士 === 淡江大學 === 物理學系 === 85 === This thesis presents a systematic study on the synthesis and the physicalproperties of the Cu-doped double perovskites Sr2Y(Ru1- xCux)O6 (2116). Its crystalline structure was determined to be of orthorhombic symmetry withspace group Pbnm by X-ray powder diffraction Rietveld method. A substantialincrease of conductivity and finally the appearance of superconductivity with Tc ranging from 10K to 60K were observed in samples with partial substitution of Ru ion by Cu in the parent antiferromagnetic insulator Sr2YRuO6. The resistive transition in the presence of magnetic field exhibits different behavior than that of the 123 cuprate superconductor. Furthermore, we observed an almost coincidence of superconducting transition temperature Tcwith an magnetic ordering temperature Tm sugggest the coexistence of superconductivity and magnetic ordering. These observed anomalous properties can be best described in termsof the"double exchange" model proposed by De Gennes.