Charge Order Lock-in by Electron-Phonon Coupling in La$_{1.675}$Eu$_{0.2}$Sr$_{0.125}$CuO$_4$

Qisi Wang; K. von Arx; M. Horio; D. John Mukkattukavil; J. Küspert; Y. Sassa; T. Schmitt; A. Nag; S. Pyon; T. Takayama; H. Takagi; M. Garcia-Fernandez; Ke-Jin Zhou; J. Chang

doi:10.1126/sciadv.abg7394

arXiv · 2012.10503

Charge Order Lock-in by Electron-Phonon Coupling in La$_{1.675}$Eu$_{0.2}$Sr$_{0.125}$CuO$_4$

Qisi Wang·K. von Arx·M. Horio·D. John Mukkattukavil·J. Küspert·Y. Sassa·T. Schmitt·A. Nag·S. Pyon·T. Takayama·H. Takagi·M. Garcia-Fernandez·Ke-Jin Zhou·J. Chang

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Abstract

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$_{1.675}$Eu$_{0.2}$Sr$_{0.125}$CuO$_4$. 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 significantly to the emergence of long-range charge-stripe order in cuprates.

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Qisi Wang, K. von Arx, M. Horio, D. John Mukkattukavil, J. Küspert, Y. Sassa, T. Schmitt, A. Nag, S. Pyon, T. Takayama, H. Takagi, M. Garcia-Fernandez, Ke-Jin Zhou, J. Chang. 2020-12-18. Charge Order Lock-in by Electron-Phonon Coupling in La$_{1.675}$Eu$_{0.2}$Sr$_{0.125}$CuO$_4$. https://doi.org/10.1126/sciadv.abg7394

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