Comment on 2501.17230 and 2502.00103 "Phonon-mediated electron attraction in SrTiO3 via the generalized Frohlich and deformation potential mechanisms" and "Theory of ab initio downfolding with arbitrary range electron-phonon coupling"

Jonathan Ruhman

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arXiv · 2503.00041

Comment on 2501.17230 and 2502.00103 "Phonon-mediated electron attraction in SrTiO3 via the generalized Frohlich and deformation potential mechanisms" and "Theory of ab initio downfolding with arbitrary range electron-phonon coupling"

Jonathan Ruhman

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Abstract

This comment critically examines the claims made in arXiv papers arXiv:2501.17230 and arXiv:2502.00103, which argue that a multiplicity of polar optical phonons can generate a long-range attractive interaction via a generalized Frohlich coupling. I identify a fundamental flaw in their derivation, showing that their result relies on an unphysical assumption--specifically, neglecting the intermode Coulomb interactions between different polar optical phonons. By restoring these missing interactions I show the screened Coulomb interaction is always repulsive in the static limit.

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Jonathan Ruhman. 2025-02-25. Comment on 2501.17230 and 2502.00103 "Phonon-mediated electron attraction in SrTiO3 via the generalized Frohlich and deformation potential mechanisms" and "Theory of ab initio downfolding with arbitrary range electron-phonon coupling". https://arxiv.org/abs/2503.00041

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