Charge order lock-in by electron-phonon coupling in La<sub>1.675</sub>Eu<sub>0.2</sub>Sr<sub>0.125</sub>CuO<sub>4</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34193430.
- Also identified by DOI 10.1126/sciadv.abg7394 and PMC identifier 8245032.
- Licence recorded as CC BY-NC.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Charge order is universal to all hole-doped cuprates. Yet, the driving interactions remain an unsolved problem. Electron-electron interaction is widely believed to be essential, whereas the role of electron-phonon interaction is unclear. We report an ultrahigh-resolution resonant inelastic x-ray scattering (RIXS) study of the in-plane bond-stretching phonon mode in stripe-ordered cuprate La<sub>1.675</sub>Eu<sub>0.2</sub>Sr<sub>0.125</sub>CuO<sub>4</sub> Phonon softening and lifetime shortening are found around the charge ordering wave vector. In addition to these self-energy effects, the electron-phonon coupling is probed by its proportionality to the RIXS cross section. We find an enhancement of the electron-phonon coupling around the charge-stripe ordering wave vector upon cooling into the low-temperature tetragonal structure phase. These results suggest that, in addition to electronic correlations, electron-phonon coupling contributes substantially to the emergence of long-range charge-stripe order in cuprates.