Born effective charges and vibrational spectra in super and bad conducting metals

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Marchese, Guglielmo, Macheda, Francesco, Binci, Luca, Calandra, Matteo, Barone, Paolo, Mauri, Francesco
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916765643046912
author Marchese, Guglielmo
Macheda, Francesco
Binci, Luca
Calandra, Matteo
Barone, Paolo
Mauri, Francesco
author_facet Marchese, Guglielmo
Macheda, Francesco
Binci, Luca
Calandra, Matteo
Barone, Paolo
Mauri, Francesco
contents Interactions mediated by electron-phonon coupling are responsible for important cooperative phenomena in metals such as superconductivity and charge-density waves. The same interaction mechanisms produce strong collision rates in the normal phase of correlated metals, causing sizeable reductions of the dc conductivity and reflectivity. As a consequence, low-energy excitations like phonons, which are crucial for materials characterization, become visible in optical infrared spectra. A quantitative assessment of vibrational resonances requires the evaluation of dynamical Born effective charges, which quantify the coupling between macroscopic electric fields and lattice deformations. We show that the Born effective charges of metals crucially depend on the collision regime of conducting electrons. In particular, we describe, within a first principles framework, the impact of electron scattering on the infrared vibrational resonances, from the undamped, collisionless regime to the overdamped, collision-dominated limit. Our approach enables the interpretation of vibrational reflectance measurements of both super and bad conducting metals, as we illustrate for the case of strongly electron-phonon coupled superhydride H$_3$S.
format Preprint
id arxiv_https___arxiv_org_abs_2303_00741
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Born effective charges and vibrational spectra in super and bad conducting metals
Marchese, Guglielmo
Macheda, Francesco
Binci, Luca
Calandra, Matteo
Barone, Paolo
Mauri, Francesco
Materials Science
Superconductivity
Interactions mediated by electron-phonon coupling are responsible for important cooperative phenomena in metals such as superconductivity and charge-density waves. The same interaction mechanisms produce strong collision rates in the normal phase of correlated metals, causing sizeable reductions of the dc conductivity and reflectivity. As a consequence, low-energy excitations like phonons, which are crucial for materials characterization, become visible in optical infrared spectra. A quantitative assessment of vibrational resonances requires the evaluation of dynamical Born effective charges, which quantify the coupling between macroscopic electric fields and lattice deformations. We show that the Born effective charges of metals crucially depend on the collision regime of conducting electrons. In particular, we describe, within a first principles framework, the impact of electron scattering on the infrared vibrational resonances, from the undamped, collisionless regime to the overdamped, collision-dominated limit. Our approach enables the interpretation of vibrational reflectance measurements of both super and bad conducting metals, as we illustrate for the case of strongly electron-phonon coupled superhydride H$_3$S.
title Born effective charges and vibrational spectra in super and bad conducting metals
topic Materials Science
Superconductivity
url https://arxiv.org/abs/2303.00741