Comment on ``Electron-phonon Vertex in the Two-dimensional One-band Hubbard Model''

B. Cerruti; E. Cappelluti; L. Pietronero

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Comment on ``Electron-phonon Vertex in the Two-dimensional One-band Hubbard Model''

B. Cerruti·E. Cappelluti·L. Pietronero

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Abstract

In cond-mat/0306131 Huang {\em et al.} reported for the first time a numerical evidence for the predominance of small phonon momenta in the electron-phonon coupling induced by electronic correlation. They report also an upturn of the electron-phonon vertex function for small momenta as function of the Hubbard repulsion $U$ for sufficient large $U$. In this comment we compare their Quantum Monte Carlo data with analytical results based on slave-boson techniques for generic $U$. We associate the upturn of the electron-phonon vertex function with the tendency towards a phase separation instability at large temperatures.

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B. Cerruti, E. Cappelluti, L. Pietronero. 2003-07-09. Comment on ``Electron-phonon Vertex in the Two-dimensional One-band Hubbard Model''. https://arxiv.org/abs/cond-mat/0307190

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