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arXiv · 2306.17287

Determination of the Spacing Between Hydrogen-Intercalated Quasi-Free-Standing Monolayer Graphene and 6H-SiC(0001) Using Total-Reflection High-Energy Positron Diffraction

Matthias Dodenhöft·Izumi Mochizuki·Ken Wada·Toshio Hyodo·Peter Richter·Philip Schädlich·Thomas Seyller·Christoph Hugenschmidt
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Abstract

We have investigated the structure of hydrogen-intercalated quasi-free-standing monolayer graphene (QFMLG) grown on 6H-SiC(0001) by employing total-reflection high-energy positron diffraction (TRHEPD). At least nine diffraction spots of the zeroth order Laue zone were resolved along <11-20> and three along <1-100>, which are assigned to graphene, SiC and higher order spots from multiple diffraction on both lattices. We further performed rocking curve analysis based on the full dynamical diffraction theory to precisely determine the spacing between QFMLG and the SiC substrate. Our study yields a spacing of d = 4.18(6)\r{A} that is in excellent agreement with the results from density-functional theory (DFT) calculations published previously.

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Matthias Dodenhöft, Izumi Mochizuki, Ken Wada, Toshio Hyodo, Peter Richter, Philip Schädlich, Thomas Seyller, Christoph Hugenschmidt. 2023-06-29. Determination of the Spacing Between Hydrogen-Intercalated Quasi-Free-Standing Monolayer Graphene and 6H-SiC(0001) Using Total-Reflection High-Energy Positron Diffraction. https://doi.org/10.1103/physrevb.108.155438

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