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Investigation of the nonlocal coherent-potential approximation

D. A. Rowlands
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Abstract

Recently the nonlocal coherent-potential approximation (NLCPA) has been introduced by Jarrell and Krishnamurthy for describing the electronic structure of substitutionally disordered systems. The NLCPA provides systematic corrections to the widely used coherent-potential approximation (CPA) whilst preserving the full symmetry of the underlying lattice. Here an analytical and systematic numerical study of the NLCPA is presented for a one-dimensional tight-binding model Hamiltonian, and comparisons with the embedded cluster method (ECM) and molecular coherent potential approximation (MCPA) are made.

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D. A. Rowlands. 2006-03-14. Investigation of the nonlocal coherent-potential approximation. https://doi.org/10.1088/0953-8984%2F18%2F12%2F003

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