Open AccessAN ALTERNATIVE DERIVATION OF COHERENT-POTENTIAL APPROXIMATION FOR DISORDERED ALLOYS-TIGHT BINDING MODEL
Author(s) -
Zhao-Qing Zhang
Publication year - 1982
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.31.285
Subject(s) - diagrammatic reasoning , coherent potential approximation , tight binding , physics , particle (ecology) , function (biology) , taylor series , amorphous solid , conductivity , statistical physics , condensed matter physics , quantum mechanics , mathematical analysis , electronic structure , mathematics , computer science , oceanography , chemistry , organic chemistry , evolutionary biology , geology , biology , programming language
The coherent-potential approximation (CPA) for both single-particle and two-particle Green's functions are rederived using locator expansion method proposed by Matsubara and Toyozawa. Instead of using self-contained cumulant expansion to treat the excluded volume effects for atoms, we use a diagrammatic method with the idea first proposed by Yonezawa. A systemmatic method is used to generate self-consistent equations for all single-site diagrams. We emphasis our treatment for two-particle Green's function which can be extended to obtain the corresponding CPA equation for electrical conductivity in liquid metals and amorphous solids.