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Densities of States, Moments, and Maximally Broken Time-Reversal Symmetry

Roger Haydock·C. M. M. Nex
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Abstract

Power moments, modified moments, and optimized moments are powerful tools for solving microscopic models of macroscopic systems; however the expansion of the density of states as a continued fraction does not converge to the macroscopic limit point-wise in energy with increasing numbers of moments. In this work the moment problem is further constrained by minimal lifetimes or maximal breaking of time-reversal symmetry, to yield approximate densities of states with point-wise macroscopic limits. This is applied numerically to models with one and two finite bands with various singularities, as well as to a model with infinite band-width, and the results are compared with the maximum entropy approximation where possible.

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Roger Haydock, C. M. M. Nex. 2006-09-20. Densities of States, Moments, and Maximally Broken Time-Reversal Symmetry. https://doi.org/10.1103/physrevb.74.205121

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