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arXiv · 2010.15958

Relaxation timescales and electron-phonon coupling in optically-pumped YBa$_2$Cu$_3$O$_{6+x}$ revealed by time-resolved Raman scattering

N. Pellatz·S. Roy·J-W. Lee·J. L. Schad·H. Kandel·N. Arndt·C. B. Eom·A. F. Kemper·D. Reznik
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Abstract

Time resolved measurements provide a new way to disentangle complex interactions in quantum materials due to their different timescales. We used pump-probe Raman scattering to investigate the apical oxygen vibration in YBa$_2$Cu$_3$O$_{6+x}$ under nonequilibrium conditions. Time-dependence of the phonon population demonstrated strong electron-phonon coupling. Most importantly, the phonon shifts to a higher energy due to transient smearing of the Fermi surface in a remarkable agreement with diagrammatic theory. We also discuss new insights into photoinduced superconductivity reported at lower doping that follow from these results.

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N. Pellatz, S. Roy, J-W. Lee, J. L. Schad, H. Kandel, N. Arndt, C. B. Eom, A. F. Kemper, D. Reznik. 2020-10-29. Relaxation timescales and electron-phonon coupling in optically-pumped YBa$_2$Cu$_3$O$_{6+x}$ revealed by time-resolved Raman scattering. https://doi.org/10.1103/physrevb.104.l180505

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