Exploratory Research for Advanced Technology, Japan Science and Technology Agency, c/o RIKEN Advanced Science Institute, Wako, Japan.
J Phys Condens Matter. 2011 Jun 22;23(24):245601. doi: 10.1088/0953-8984/23/24/245601. Epub 2011 Jun 1.
A large-size single crystal of nearly stoichiometric SrCoO(3) was prepared with a two-step method combining the floating-zone technique and subsequent high oxygen pressure treatment. SrCoO(3) crystallizes in a cubic perovskite structure with space group Pm3m, and displays an itinerant ferromagnetic behavior with the Curie temperature of 305 K. The easy magnetization axis is found to be along the [111] direction, and the saturation moment is 2.5 µ(B)/f.u., in accord with the picture of the intermediate spin state. The resistivity at low temperatures (T) is proportional to T(2), indicative of the possible effect of orbital fluctuation in the intermediate spin ferromagnetic metallic state. Unusual anisotropic magnetoresistance is also observed and its possible origin is discussed.
采用浮区法结合后续高氧压处理的两步法制备了近乎化学计量比的 SrCoO(3) 大型单晶。SrCoO(3) 具有立方钙钛矿结构,空间群为 Pm3m,表现出巡游铁磁行为,居里温度为 305 K。易磁化轴被发现沿[111]方向,饱和磁矩为 2.5 µ(B)/f.u.,符合中间自旋态的图像。低温(T)下的电阻率与 T(2)成正比,表明在中间自旋铁磁金属态中轨道波动可能有影响。还观察到异常各向异性磁阻,讨论了其可能的起源。