Unified Method of Electronic Structure Calculation Using Green Function Method

我们开发了一个通用的绿色函数电子结构计算软件包。还提供了一本手册和一些注意事项。绿色函数方法对于超结构效应、无序效应和掺杂效应是必不可少的系统是非常有用的。绿色函数方法可以很容易地应用于这样的系统。我们应用KKR和KKR-CPA-LDA程序包研究了以下问题：（1）用KKR-CPA-LDA程序包研究了稀磁半导体的混晶和超晶格。在这种情况下，为了描述自旋玻璃态和铁磁态，不仅要考虑化学无序，还要考虑磁无序，即上下原子磁矩的随机排列。事实证明，我们的一揽子计划在处理这类系统方面是强大的。(2)本文用KKR程序包计算了Cr/Fe超晶格的电子结构。特别是，我们测试了除了向量化之外的并行计算。基准最终记录了300倍左右的加速，这超过了预期。(3)黄铁矿型硫属化合物混晶的处理。使用KKR-CPA-LDA封装。为了处理这种系统的开放结构，我们开发了一种方法，使我们能够引入许多空球。这最终大大提高了计算的准确性。

We have developed a general package for electronic structure calculation using the Green's function method. A manual and some notes are also provided. The Green's function method is very useful for the systems where the superstructure, disorder, and doping effects are essential. The Green's function method can be easily applied for such systems. We have applied the KKR package and KKR-CPA-LDA packages on the following problems :(1) Mixed crystals and super-lattices of diluted-magnetic-semiconductors are investigated by use of the KKR-CPA-LDA package. In this case, not only the chemical disorder but also the magnetic disorder, namely, the random arrangement of up and down atomic magnetic moments should be treated in order to describe the spin-glass states as well as the ferromagnetic one. Our package turned out to be powerful in treating such systems.(2) We have calculated the electronic structure of Cr/Fe super lattices by use of the KKR package. In particular, we tested the parallel computing in addition to the vectorization. The benchmark finally recorded the acceleration of around factor 300, which is more than expected.(3) Pyrite-type chalcogenide mixed crystals are treated. by use of the KKR-CPA-LDA package. In order to treat the open structure for such systems, we developed a method that enables us to introduce many empty spheres. This finally increases the accuracy of the calculation greatly.