17O and 63Cu NMR Investigations of High-Tc SuperconductorLa1.85Sr0.15CuO4 with Tc=38 K
17O and 63Cu NMR Investigations of High-Tc SuperconductorLa1.85Sr0.15CuO4 with Tc=38 K
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Tc=38 K 高温超导体 La1.85Sr0.15CuO4 的 17O 和 63Cu NMR 研究
DOI：
10.1143/jpsj.60.3516
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发表时间：
1991
影响因子：
1.7
通讯作者：
K. Asayama
中科院分区：
文献类型：
--
作者：
K. Ishida;Y. Kitaoka;G. Zheng;K. Asayama
17 O和63 Cu NMR测量已在T c =38 K的L 1.85 Sr 0.15 CuO 4 中进行。17 O奈特位移和四极张量均通过对取向粉末的17 O谱的分析来确定。 Hanzawa 等人的分析一致地解释了平面氧和 Cu 原子核的四极频率。由YBa 2 Cu 3 O 7 制成，由于Cu和O位点上的现场空穴而具有电场梯度。然后推导了Cu-3 d (x 2 - y 2 )和2 p } σ波函数的权重因子，其中后者权重较大。从 Knight 位移与体磁化率图来看， 17 O 和 63 Cu 的超精细耦合常数与 YBa 2 Cu 3 O 7 中的超精细耦合常数几乎相同。两个位移均显着降低至低于T c ，在4.2 K时具有63 K ab =0.38%和17 K c =0.02%的残余部分，这大于YBa 2 Cu 3 O 7 中的残余部分。
17 O and 63 Cu NMR measurements have been made in L 1.85 Sr 0.15 CuO 4 with T c =38 K. Both 17 O Knight shift and quadrupole tensor were determined from the analyses of the 17 O spectrum of oriented powder. The quadrupole frequencies of the planar oxygen and Cu nuclei are consistently interpreted by the analyses of Hanzawa et al . made in YBa 2 Cu 3 O 7 with the electric field gradients due to the on-site holes at Cu and O sites. Then the weight factor of the Cu-3 d ( x 2 - y 2 ) and 2 p } σ wave functions are deduced, the latter having the larger weight. From the Knight shifts vs the bulk susceptibility plots, the hyperfine coupling constants for 17 O and 63 Cu were almost the same as those in YBa 2 Cu 3 O 7 . Both shifts decrease significantly below T c having residual parts of 63 K ab =0.38% and 17 K c =0.02% at 4.2 K, which were larger than those in YBa 2 Cu 3 O 7 .