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>
Qisi Wang, Karin von Arx, Masafumi Horio, Deepak John Mukkattukavil, J. Küspert, Yasmine Sassa, Thorsten Schmitt, Abhishek Nag, Sunseng Pyon, T. Takayama, H. Takagi, Mirian García‐Fernández, Ke‐Jin Zhou, J. Chang
Abstract
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.