Electron-phonon coupling revealed by charge density fluctuations in cuprate superconductors

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Fedele, Martina, Merzoni, Giacomo, Sala, Marco Moretti, Rosa, Francesco, Brookes, Nicholas B., Lombardi, Floriana, Caprara, Sergio, Ghiringhelli, Giacomo, Arpaia, Riccardo
Format: Preprint
Veröffentlicht: 2026
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866912915609616384
author Fedele, Martina
Merzoni, Giacomo
Sala, Marco Moretti
Rosa, Francesco
Brookes, Nicholas B.
Lombardi, Floriana
Caprara, Sergio
Ghiringhelli, Giacomo
Arpaia, Riccardo
author_facet Fedele, Martina
Merzoni, Giacomo
Sala, Marco Moretti
Rosa, Francesco
Brookes, Nicholas B.
Lombardi, Floriana
Caprara, Sergio
Ghiringhelli, Giacomo
Arpaia, Riccardo
contents Electron-phonon coupling (EPC) governs lattice dynamics, charge transport, and collective electronic phases in quantum materials. In several families of unconventional superconductors, including transition-metal dichalcogenides and kagome metals, growing evidence points to a cooperative role of EPC and dynamic charge-density fluctuations (CDF) in stabilizing superconductivity. However, how the EPC strength evolves across phase diagrams and relates to superconducting properties in strongly correlated systems remains an open question. Here we investigate the interplay between phonons and the CDF recently identified in cuprate superconductors. Using resonant inelastic x-ray scattering, we track the dispersion and intensity of bond-stretching phonons in YBa$_2$Cu$_3$O$_{7-δ}$ over wide ranges of doping, temperature, and momentum. We find that both the phonon softening at the CDF wave vector and the EPC strength, extracted from a pronounced phonon intensity anomaly, are maximized near $p = 0.19$, where superconducting properties are optimal and CDF intensity is strongest. These results identify dynamic charge-density fluctuations, rather than quasi-static charge density waves, as the dominant source of phonon renormalization in cuprates, and establish a direct correlation between EPC strength and the superconducting dome. More broadly, our measurements highlight EPC as a doping-dependent property of correlated materials, shaped by the electronic environment in which lattice vibrations are embedded.
format Preprint
id arxiv_https___arxiv_org_abs_2602_18112
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Electron-phonon coupling revealed by charge density fluctuations in cuprate superconductors
Fedele, Martina
Merzoni, Giacomo
Sala, Marco Moretti
Rosa, Francesco
Brookes, Nicholas B.
Lombardi, Floriana
Caprara, Sergio
Ghiringhelli, Giacomo
Arpaia, Riccardo
Superconductivity
Strongly Correlated Electrons
Electron-phonon coupling (EPC) governs lattice dynamics, charge transport, and collective electronic phases in quantum materials. In several families of unconventional superconductors, including transition-metal dichalcogenides and kagome metals, growing evidence points to a cooperative role of EPC and dynamic charge-density fluctuations (CDF) in stabilizing superconductivity. However, how the EPC strength evolves across phase diagrams and relates to superconducting properties in strongly correlated systems remains an open question. Here we investigate the interplay between phonons and the CDF recently identified in cuprate superconductors. Using resonant inelastic x-ray scattering, we track the dispersion and intensity of bond-stretching phonons in YBa$_2$Cu$_3$O$_{7-δ}$ over wide ranges of doping, temperature, and momentum. We find that both the phonon softening at the CDF wave vector and the EPC strength, extracted from a pronounced phonon intensity anomaly, are maximized near $p = 0.19$, where superconducting properties are optimal and CDF intensity is strongest. These results identify dynamic charge-density fluctuations, rather than quasi-static charge density waves, as the dominant source of phonon renormalization in cuprates, and establish a direct correlation between EPC strength and the superconducting dome. More broadly, our measurements highlight EPC as a doping-dependent property of correlated materials, shaped by the electronic environment in which lattice vibrations are embedded.
title Electron-phonon coupling revealed by charge density fluctuations in cuprate superconductors
topic Superconductivity
Strongly Correlated Electrons
url https://arxiv.org/abs/2602.18112