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arXiv 1703.04366cond-mat.supr-con
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铜氧化物超导体中NMR位移的对比唯象

Contrasting Phenomenology of NMR Shifts in Cuprate Superconductors

Jürgen Haase, Michael Jurkutat, Jonas Kohlrautz

摘要:

核磁共振(NMR)位移,如果剥离其不确定性,必须持有关于铜氧化物中的电子流体的关键信息。将回顾有利于单一流体场景的早期转变解释,以及最近报告其失败的实验。此后,基于文献的平面铜的位移数据的对比的铜酸盐超导体的位移现象的发展,这是非常不同的早期的观点,而与所有已发表的数据一致。例如,它将表明,迄今为止使用的超精细的情况是不够的,因为一个大的各向同性位移分量被发现。此外,在超导转变温度之上和之下的位移的温度依赖性的变化根据之前未讨论的一些规则进行。如果磁场位于CuO $_2$平面内,则在最低温度下似乎可以存在显著的自旋位移,这指向自旋在$3d(x^2-y^2)$轨道中的局部化。一个简单的模型是基于最基本的调查结果。分析必须有新的后果的理论铜。

英文摘要:

Nuclear magnetic resonance (NMR) shifts, if stripped off their uncertainties, must hold key information about the electronic fluid in the cuprates. The early shift interpretation that favored a single-fluid scenario will be reviewed, as well as recent experiments that reported its failure. Thereafter, based on literature shift data for planar Cu a contrasting shift phenomenology for cuprate superconductors is developed, which is very different from the early view while being in agreement with all published data. For example, it will be shown that the hitherto used hyperfine scenario is inadequate as a large isotropic shift component is discovered. Furthermore, the changes of the temperature dependences of the shifts above and below the superconducting transitions temperature proceed according to a few rules that were not discussed before. It appears that there can be substantial spin shift at the lowest temperature if the magnetic field lies in the CuO$_2$ plane, which points to a localization of spin in the $3d(x^2-y^2)$ orbital. A simple model is presented based on the most fundamental findings. The analysis must have new consequences for theory of the cuprates.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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