Closed-form solutions to surface Green's functions
Closed-form solutions to surface Green's functions
复制标题
DOI：
10.1103/physrevb.55.5266
复制
发表时间：
1997-02
影响因子：
3.7
通讯作者：
A. Umerski
中科院分区：
文献类型：
--
作者：
A. Umerski
我们获得了封闭形式的解析解的表面绿色的功能在任意多轨道模型。该公式是完全通用的，并且对于经验紧束缚、线性muffintin轨道紧束缚、屏蔽Korringa-Kohn-Rostoker和其他绿色函数等价形式主义同样有效，其中哈密顿量可以被放入局部化的（即，块带）形式。这些解适用于有限或半无限表面系统，具有相当一般的衬底和覆盖层，甚至适用于超晶格。这是通过求解戴森方程的Moebius变换的矩阵值的扩展。讨论了解的解析性质，并通过考虑解的渐近极限，得到了精确（半无限）曲面绿色函数的一个简单的封闭形式。表面绿色的功能（或可观察到的量，如状态密度），使用这种封闭的形式的数值计算与以前已知的迭代程序进行比较。我们发现它比最好的迭代方法更快，更稳定，更准确。{版权} {美国物理学会}
We obtain closed-form analytic solutions for surface Green`s functions within arbitrary multiorbital models. The formulation is completely general, and is equally valid for empirical tight binding, linear-muffin-tin-orbital tight binding, screened Korringa-Kohn-Rostoker and other Green`s-function equivalent formalisms, where the Hamiltonian can be put into a localized (i.e., block-band) form. The solutions are applicable to finite or semi-infinite surface systems, with quite general substrate and overlayers, or even to superlattices. This is achieved by solving Dyson`s equations by means of a matrix-valued extension of the Moebius transformation. The analytical properties of the solutions are discussed, and by considering their asymptotic limit, a simple closed form for the exact (semi-infinite) surface Green`s function is obtained. The numerical calculation of the surface Green`s function (or of observable quantities such as the density of states) using this closed form is compared with previously known iterative procedures. We find that it is far faster, far more stable, and more accurate than the best iterative method. {copyright} {ital 1997} {ital The American Physical Society}