Crystal Growth, Structure, and Transport Properties of the Five-Leg Spin Ladder Compound La8Cu7O19
Crystal Growth, Structure, and Transport Properties of the Five-Leg Spin Ladder Compound La8Cu7O19
复制标题
五足自旋梯化合物 La8Cu7O19 的晶体生长、结构和输运特性
DOI：
10.1006/jssc.2000.9017
复制
发表时间：
2001
影响因子：
5.4
通讯作者：
J. Akimitsu
中科院分区：
文献类型：
--
作者：
C. Sekar;Takao Watanabe;A. Matsuda;H. Shibata;Y. Zenitani;J. Akimitsu
在空气环境中，La2O3-CuO体系中La8Cu7O19的晶化区存在于较窄的温度(1045~1050℃)和组成范围(1：4.5~1：5.0；La2O3：CuO摩尔比)。在这个窄范围内，我们首次用改进的慢冷方法成功地生长出大尺寸的La_8Cu7O_(19)单晶。单晶X射线衍射分析表明，La8Cu7O19为单斜晶系，空间群为C2/c，晶胞参数为a=13.82(7)A，b=3.734(8)A，c=34.77(10)A，β=99.3(4)°。生长的空穴掺杂La8Cu7O19单晶的电输运行为是半导化的。在293K时，空穴掺杂样品的最低电阻率为11.0mΩ-cm，沿梯形方向(∥b轴)。
Abstract The crystallization region of La 8 Cu 7 O 19 exists in a narrow temperature (1045–1050°C) and composition range (1:4.5– 1:5.0; La 2 O 3 :CuO molar ratio) in the La 2 O 3 –CuO system in an air ambient. In this narrow range, we have succeeded in growing large La 8 Cu 7 O 19 single crystals, for the first time, by a modified slow cooling method. Single-crystal X-ray diffraction analysis reveals that La 8 Cu 7 O 19 crystallizes in a monoclinic structure with space group C 2/ c and has the lattice parameters a =13.82(7) A, b =3.734(8) A, c =34.77(10) A, and β =99.3(4)°. The electrical transport behavior of the as-grown and hole-doped La 8 Cu 7 O 19 single crystals are semiconducting. A lowest resistivity of 11.0 mΩ-cm is measured at 293 K along the ladder direction (∥ b -axis) for the hole-doped samples.