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arXiv · 1902.09163

Experimental Determination of Momentum-Resolved Electron-Phonon Coupling

Matteo Rossi·Riccardo Arpaia·Roberto Fumagalli·Marco Moretti Sala·Davide Betto·Gabriella M. De Luca·Kurt Kummer·Jeroen van den Brink·Marco Salluzzo·Nicholas B. Brookes·Lucio Braicovich·Giacomo Ghiringhelli
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Abstract

We provide a novel experimental method to quantitatively estimate the electron-phonon coupling and its momentum dependence from resonant inelastic x-ray scattering (RIXS) spectra based on the detuning of the incident photon energy away from an absorption resonance. We apply it to the cuprate parent compound NdBa$_2$Cu$_3$O$_6$ and find that the electronic coupling to the oxygen half-breathing phonon mode is strongest at the Brillouin zone boundary, where it amounts to $\sim 0.17$ eV, in agreement with previous studies. In principle, this method is applicable to any absorption resonance suitable for RIXS measurements and will help to define the contribution of lattice vibrations to the peculiar properties of quantum materials.

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Matteo Rossi, Riccardo Arpaia, Roberto Fumagalli, Marco Moretti Sala, Davide Betto, Gabriella M. De Luca, Kurt Kummer, Jeroen van den Brink, Marco Salluzzo, Nicholas B. Brookes, Lucio Braicovich, Giacomo Ghiringhelli. 2019-02-25. Experimental Determination of Momentum-Resolved Electron-Phonon Coupling. https://doi.org/10.1103/physrevlett.123.027001

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