Correlated electron systems, particularly iron-based superconductors, are extremely sensitive to strain, which inevitably occurs in the crystal growth process. Built-in strain of this type has been proposed as a possible explanation for experiments where nematic order has been observed at high temperatures corresponding to the nominally tetragonal phase of iron-based superconductors. Strain is assumed to produce linear defect structures, e.g., dislocations, which are quite similar to O vacancy chainlets in the underdoped cuprate superconductor YBCO. Here we investigate a simple microscopic model of dislocations in the presence of electronic correlations which create defect states that can drive magnetic anisotropy of this kind, if spin-orbit interaction is present. We estimate the contribution of these dislocations to magnetic anisotropy as detected by current torque magnetometry experiments in both cuprates and Fe-based systems.

中文翻译：

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相关电子系统中线性缺陷结构的磁各向异性

相关的电子系统，特别是铁基超导体，对应变极其敏感，这在晶体生长过程中不可避免地发生。这种类型的内置应变已被提议作为对在高温下观察到与铁基超导体标称四方相相对应的向列有序的实验的可能解释。假定应变会产生线性缺陷结构，例如位错，这与低掺杂铜酸盐超导体 YBCO 中的 O 空位链非常相似。在这里，我们研究了在存在电子相关性的情况下位错的简单微观模型，如果存在自旋轨道相互作用，则该模型会产生可以驱动这种磁各向异性的缺陷状态。