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arXiv 2606.28906cond-mat.supr-con
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铜氧化物高温超导理论

Theory of High-Tc Superconductivity in Cuprates

Universidade Federal do Rio de Janeiro(里约热内卢联邦大学)

E. C. Marino

AI总结:

本文基于自旋-费米-哈伯德模型,通过将铜离子电子视为局域自旋、掺杂空穴在氧子晶格上运动并发生近藤相互作用,成功解释了空穴掺杂铜氧化物的高温超导现象。

摘要:

铜氧化物高温超导现象的基本物理过程发生在这些材料中的$CuO_2$平面内。属于这些平面的活性电子的动力学由三带哈伯德模型(3BHM)很好地描述。然而,该模型的复杂性促使研究人员寻找更简单但仍相关的替代方案。为了规避该模型的复杂性,考虑了(3BHM)的两个主要简化版本。在第一种替代方案中,通过将掺杂空穴及其各自的子晶格与$Cu^{++}$电子结合,形成所谓的张-瑞单态,从而消除它们。剩余的动力学包括掺杂莫特-哈伯德绝缘体,并由t-J模型描述。第二种替代方案认为$Cu^{++}$电子形成局域自旋的方格子,而掺杂空穴沿氧子晶格运动,并经历与局域自旋的近藤类磁相互作用,此外还有哈伯德类电排斥。这种情景由自旋-费米-哈伯德模型描述。该领域的大多数研究人员选择走第一条路,而我选择了第二条。在本文中,我详细回顾了为什么这一选择导致了空穴掺杂铜氧化物高温超导的成功理论。

英文摘要:

The essential physical processes underlying the phenomenon of High-Tc superconductivity in cuprates occur in the $CuO_2$ planes, found in these materials. The dynamics of the active electrons belonging to such planes is well described by the Three Bands Hubbard Model (3BHM). The complexity of such model, however, led the researchers to look for simpler and yet relevant alternatives. In the attempts to circumvent the complexity of this model,two main simplified versions of the (3BHM) were considered. In the first alternative, one eliminates the doped holes and their respective sub-lattices by tying them to the $Cu^{++}$ electrons, thereby forming the so called Zhang-Rice singlets. The remaining dynamics consists in doping a Mott-Hubbard insulator and is described by the t-J Model. The second alternative maintains that the $Cu^{++}$ electrons form a square lattice of localized spins, while the doped holes move along the oxygen sub-lattices and undergo a Kondo like magnetic interaction with the localized spins, besides the Hubbard-like electric repulsion. This scenario is described by the Spin-Fermion-Hubbard Model. Most of the researchers in the field chose to follow the first road, while, I chose the second one. In this article I review in detail the reasons why that choice has led to a successful theory for High-Tc superconductivity in hole doped 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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