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Optimized phonon approach for the diagonalization of electron-phonon problems

A. Weisse·H. Fehske·G. Wellein·A. R. Bishop
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Abstract

We propose a new optimized phonon approach for the numerical diagonalization of interacting electron-phonon systems combining density-matrix and Lanczos algorithms. We demonstrate the reliablity of this approach by calculating the phase diagram for bi-polaron formation in the one-dimensional Holstein-Hubbard model, and the Luttinger parameters for the metallic phase of the half-filled one-dimensional Holstein model of spinless fermions.

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A. Weisse, H. Fehske, G. Wellein, A. R. Bishop. 2000-03-08. Optimized phonon approach for the diagonalization of electron-phonon problems. https://doi.org/10.1103/physrevb.62.r747

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