Pade Approximants and the Calculation of Spectral Functions of Solids

摘要

The computational approach of Chisholm, Genz and Pusterla for evaluating Feynman matrix elements in the physical region, is proposed for the calculation of spectral functions of solids. The method is based on the moment expansion of the functions, with a convenient choice of reference point, and its resummation with Pade approximants. The technique is tested in the calculation of the electron density of states for a one-dimensional system. In this case, the convergence of the method may be formally proved, while a numerical study shows its practical signification. (Atomindex citation 13:712259)