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arXiv · 1608.01045

Epitaxial growth and electronic properties of mixed valence YbAl3 thin films

Shouvik Chatterjee·Suk Hyun Sung·David J. Baek·Lena F. Kourkoutis·Darrell G. Schlom·Kyle M. Shen
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Abstract

We report the growth of thin films of the mixed valence compound YbAl$_{3}$ on MgO using molecular-beam epitaxy. Employing an aluminum buffer layer, epitaxial (001) films can be grown with sub-nm surface roughness. Using x-ray diffraction, in situ low-energy electron diffraction and aberration-corrected scanning transmission electron microscopy we establish that the films are ordered in the bulk as well as at the surface. Our films show a coherence temperature of 37 K, comparable to that reported for bulk single crystals. Photoelectron spectroscopy reveals contributions from both $\textit{f}^{13}$ and $\textit{f}^{12}$ final states establishing that YbAl$_{3}$ is a mixed valence compound and shows the presence of a Kondo Resonance peak near the Fermi-level.

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Shouvik Chatterjee, Suk Hyun Sung, David J. Baek, Lena F. Kourkoutis, Darrell G. Schlom, Kyle M. Shen. 2016-08-03. Epitaxial growth and electronic properties of mixed valence YbAl3 thin films. https://doi.org/10.1063/1.4958336

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