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Nonlocal spectral properties of disordered alloys

G. M. Batt·D. A. Rowlands
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Abstract

A general method is proposed for calculating a fully k-dependent, continuous, and causal spectral function A(k,E) within the recently introduced nonlocal version of the coherent-potential approximation (NLCPA). The method involves the combination of both periodic and anti-periodic solutions to the associated cluster problem and also leads to correct bulk quantities for small cluster sizes. We illustrate the method by investigating the Fermi surface of a two-dimensional alloy. Dramatically, we find a smeared electronic topological transition not predicted by the conventional CPA.

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G. M. Batt, D. A. Rowlands. 2006-10-08. Nonlocal spectral properties of disordered alloys. https://doi.org/10.1088/0953-8984%2F18%2F48%2F031

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