Tight-binding Hamiltonians for high-temperature superconductors and applications to coherent-potential-approximation calculations of the electronic properties of La2-xBaxCuO4-y.
Tight-binding Hamiltonians for high-temperature superconductors and applications to coherent-potential-approximation calculations of the electronic properties of La2-xBaxCuO4-y.
复制标题
高温超导体的紧束缚哈密顿量及其在 La2-xBaxCuO4-y 电子性质的相干势近似计算中的应用。
DOI：
10.1103/physrevb.39.4235
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Pickett
中科院分区：
文献类型：
--
作者：
DeWeert;Papaconstantopoulos;Pickett
我们提出了精确的紧束缚参数化的第一原理增广平面波或线性增广平面波带结构的LaCuO 3，La 2 CuO 4，Ba 2 CuO 4，和高温超导体YBa 2 Cu 3 O 7。我们讨论了这些拟合的方法和有效应用，包括作为一个例子，我们的紧束缚相干势近似（CPA）计算的无序对La 2− x Ba x CuO 4− y的电子结构的影响。我们的CPA计算支持了La 2− x Ba x CuO 4的费米能级的刚性带降低的假设，从而提高了那里的态密度。然而，对于La 2 BaCuO 4− y，它们产生了有趣的结果，即氧空位也降低了EF，提高了N（EF）。这对这些材料的超导理论是一个重要的结果。除了CPA计算，我们的参数化的能带结构应该被证明是一个有用的工具，其他的研究，这将提高我们对这些材料的理解。
We present accurate tight-binding parametrizations of the first-principles augmented-plane-wave or linear-augmented-plane-wave band structures of LaCuO 3, La 2 CuO 4, Ba 2 CuO 4, and the high-temperature superconductor YBa 2 Cu 3 O 7. We discuss the methodology and efficient application of these fits, including as an example our tight-binding coherent-potential-approximation (CPA) calculations of the effects of disorder on the electronic structure of La 2− x Ba x CuO 4− y. Our CPA calculations support the hypothesis of a rigid-band lowering of the Fermi level for La 2− x Ba x CuO 4, enhancing the density of states there. However, for La 2 BaCuO 4− y they yield the interesting result that oxygen vacancies also lower E F and raise N (E F). This is a significant result for the theory of superconductivity in these materials. In addition to CPA calculations, our parametrizations of the band structures should prove to be a useful tool for other studies which will enhance our understanding of these materials.