Cluster Approximation for Disordered Systems
- 1 June 1974
- journal article
- Published by Oxford University Press (OUP) in Progress of Theoretical Physics
- Vol. 51 (6) , 1678-1693
- https://doi.org/10.1143/ptp.51.1678
Abstract
A theory of cluster approximation for disordered systems with diagonal disorder is developed. The one-particle and two-particle Green's functions are obtained. Both locator and propagator formalisms give the same result. It is shown that Ward's identity is satisfied in this theory and our theory reproduces the coherent potential approximation when the cluster is made of a single-site. As an example, numerical calculations of the density of states for vibrations in one-dimensional random lattice are carried out by taking into account the cluster of five atoms, and a peaky structure is found, as was shown in the computer simulation by Dean.Keywords
This publication has 1 reference indexed in Scilit:
- Vibrational spectra of diatomic chains. IIProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1961