The influence of phonon symmetry and electronic structure on the electron-phonon coupling momentum dependence in cuprates
Artikel i vetenskaplig tidskrift, 2026
The experimental determination of the magnitude and momentum dependence of electron-phonon coupling (EPC) is an outstanding problem in condensed matter physics. The intensity of phonon peaks in Resonant Inelastic X-ray Scattering (RIXS) spectra can be related to the underlying EPC strength under significant approximations whose validity deserves careful verification. We measured the Cu L3 RIXS phonon intensity as a function of incident photon energy and momentum transfer in several layered cuprates. For CaCuO2, La2−xSrxCuO4+δ, and YBa2Cu3O6, using a generally accepted theoretical model, we quantitatively estimate the EPC for the bond-stretching mode along the high-symmetry directions (ζ,0) and (ζ,ζ), and as a function of the azimuthal angle φ at fixed q∥. We compare our results with theoretical predictions and find that the q∥-dependence of the phonon RIXS intensity can be largely ascribed to the phonon symmetry. However, a more satisfactory prediction of the experimental results requires an accurate description of the electronic structure close to the Fermi level. Our extensive investigation indicates that Cu L3 RIXS can reliably determine the momentum dependence of EPC for the bond-stretching modes of cuprates. Moreover, the large experimental basis provided here constitutes a stringent test for advanced theoretical predictions on the EPC.
Författare
Maryia Zinouyeva
Politecnico di Milano
R. Heid
Karlsruher Institut für Technologie (KIT)
Giacomo Merzoni
European XFEL
Politecnico di Milano
Riccardo Arpaia
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Universita Ca' Foscari Venezia
Nikolai Andreev
Universita degli Studi di Roma Tor Vergata
Marco Biagi
Universita Ca' Foscari Venezia
Politecnico di Milano
Nicholas B. Brookes
European Synchrotron Radiation Facility (ESRF)
D. Di Castro
Universita degli Studi di Roma Tor Vergata
Alexei Kalaboukhov
Universita Ca' Foscari Venezia
Kurt Kummer
European Synchrotron Radiation Facility (ESRF)
Floriana Lombardi
Universita Ca' Foscari Venezia
L. Martinelli
Politecnico di Milano
Universität Zürich
Francesco Rosa
Politecnico di Milano
Matteo Rossi
Politecnico di Milano
F. Yakhou-Harris
European Synchrotron Radiation Facility (ESRF)
Lucio Braicovich
European Synchrotron Radiation Facility (ESRF)
Politecnico di Milano
Marco Moretti
Politecnico di Milano
Paolo G. Radaelli
University of Oxford
Giacomo Ghiringhelli
Politecnico di Milano
npj Quantum Materials
23974648 (eISSN)
Vol. 11 1 30Resonant inelastisk röntgenspridning för att studera förändringar i högtemperatursupraledares fasdiagram orsakade av mekanisk påfrestning och inneslutning
Vetenskapsrådet (VR) (2020-04945), 2021-01-01 -- 2024-12-31.
Ämneskategorier (SSIF 2025)
Atom- och molekylfysik och optik
Den kondenserade materiens fysik
Annan fysik
DOI
10.1038/s41535-026-00863-x