Environmental control of electron-phonon coupling in barium doped graphene

Autor(en)

N. I. Verbitskiy, A. V. Fedorov, C. Tresca, G. Profeta, L. Petaccia, B. V. Senkovskiy, D. Yu Usachov, D. V. Vyalikh, L. V. Yashina, A. A. Eliseev, T. Pichler, A. Grüneis

Abstrakt

Two-dimensional superconductivity in alkali-and alkaline-Earth-metal doped monolayer graphene has been explained in the framework of electron-phonon coupling (EPC) and experiments yielded superconducting transition temperatures (TC) up to 6 K. In contrast to bulk graphite intercalation compounds, the interface of doped graphene with its environment affects its physical properties. Here we present a novel and well-defined BaC8 interface structure in Ba-doped single-layer graphene on Au and Ge substrates. We use angle-resolved photoemission spectroscopy in combination with ab initio modelling to extract the Eliashberg function and EPC for both substrates. This allows us to quantitatively assess the environmental effects for both Au and Ge substrates on superconductivity in graphene. We show that for semiconducting Ge substrates, the doping level and EPC are higher. Our study highlights that both dopant order and the metallicity of the substrate can be used to control EPC and hence superconductivity.

Organisation(en)

Elektronische Materialeigenschaften

Externe Organisation(en)

Universität zu Köln, Lomonosov Moscow State University (MSU), Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Saint Petersburg State University, Università degli Studi dell’Aquila, Consiglio Nazionale delle Ricerche, Elettra Sincrotrone Trieste, Technische Universität Dresden

Journal

2D Materials

Band

3

Anzahl der Seiten

7

ISSN

2053-1583

DOI

https://doi.org/10.1088/2053-1583/3/4/045003

Publikationsdatum

12-2016

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Schlagwörter

ASJC Scopus Sachgebiete

Condensed Matter Physics, Mechanics of Materials, Mechanical Engineering, Allgemeine Chemie, Allgemeine Materialwissenschaften

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/e8338896-50f6-4108-8d92-6533f82fd22e