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Density-Matrix Algorithm for Phonon Hilbert Space Reduction in the Numerical Diagonalization of Quantum Many-Body Systems

Alexander Weiße·Gerhard Wellein·Holger Fehske
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Abstract

Combining density-matrix and Lanczos algorithms we propose a new optimized phonon approach for finite-cluster diagonalizations of interacting electron-phonon systems. To illustrate the efficiency and reliability of our method, we investigate the problem of bipolaron band formation in the extended Holstein Hubbard model.

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Alexander Weiße, Gerhard Wellein, Holger Fehske. 2001-04-27. Density-Matrix Algorithm for Phonon Hilbert Space Reduction in the Numerical Diagonalization of Quantum Many-Body Systems. https://doi.org/10.1007/978-3-642-56034-7_12

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