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arXiv · 2007.09387

Concomitant enhancement of electron-phonon coupling and electron-electron interaction in graphene decorated with ytterbium

Minhee Kang·Jinwoong Hwang·Ji-Eun Lee·Alexei Fedorov·Choongyu Hwang
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Abstract

The interplay between electron-electron interaction and electron-phonon coupling has been one of the key issues in graphene as it can provide information on the origin of enhanced electron-phonon coupling in graphene by foreign atoms. In ytterbium-decorated graphene on SiC substrate, electron-phonon coupling exhibits strong enhancement compared to that of as-grown graphene. Based on angle-resolved photoemission study, the presence of ytterbium is also found to result in the decrease of Fermi velocity, revealing the enhancement of electron-electron interaction within the Fermi liquid theory. Our finding on the concomitant enhancement of electron-electron interaction and electron-phonon coupling suggests a possibility of the interplay between the two representative many-body interactions in graphene decorated with foreign atoms.

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Minhee Kang, Jinwoong Hwang, Ji-Eun Lee, Alexei Fedorov, Choongyu Hwang. 2020-07-18. Concomitant enhancement of electron-phonon coupling and electron-electron interaction in graphene decorated with ytterbium. https://doi.org/10.1016/j.apsusc.2018.10.134

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