I. Physikalisches Institut, Justus Liebig University, Giessen, Germany.
J Phys Condens Matter. 2013 Oct 23;25(42):425301. doi: 10.1088/0953-8984/25/42/425301. Epub 2013 Sep 27.
The theoretical description of modern nanoelectronic devices requires a quantum mechanical treatment and often involves disorder, e.g. from alloys. Therefore, the ab initio theory of transport using non-equilibrium Green's functions is extended to the case of disorder described by the coherent potential approximation. This requires the calculation of non-equilibrium vertex corrections. We implement the vertex corrections in a Korringa-Kohn-Rostoker multiple scattering scheme. In order to verify our implementation and to demonstrate the accuracy and applicability we investigate a system of an iron-cobalt alloy layer embedded in copper. The results obtained with the coherent potential approximation are compared to supercell calculations. It turns out that vertex corrections play an important role for this system.
现代纳米电子器件的理论描述需要量子力学处理，并且通常涉及无序，例如来自合金。因此，使用非平衡格林函数的输运的第一性原理理论被扩展到由相干势近似描述的无序情况。这需要计算非平衡顶点修正。我们在 Korringa-Kohn-Rostoker 多重散射方案中实现了顶点修正。为了验证我们的实现并展示准确性和适用性，我们研究了嵌入在铜中的铁钴合金层的系统。用相干势近似得到的结果与超胞计算进行了比较。结果表明，对于这个系统，顶点修正起着重要的作用。
