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arXiv · 1711.08300

Coexistence of strongly buckled germanene phases on Al(111)

W. Wang·R. I. G. Uhrberg
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Abstract

We report a study of structural and electronic properties of a germanium layer on Al(111) using scanning tunneling microscopy (STM), low energy electron diffraction and core-level photoelectron spectroscopy. Experimental results show that a germanium layer can be formed at a relatively high substrate temperature showing either (3$\times$3) or ($\sqrt{7}$$\times$$\sqrt{7}$)R$\pm$19.1° reconstructions. First-principles calculations based on density functional theory suggest an atomic model consisting of a strongly buckled (2$\times$2) germanene layer, which is stable in two different orientations on Al(111). Simulated STM of both orientations fit nicely with experimental STM images and the Ge 3d core-level data decomposed into four components is consistent with the suggested model.

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W. Wang, R. I. G. Uhrberg. 2017-12-07. Coexistence of strongly buckled germanene phases on Al(111). https://doi.org/10.3762/bjnano.8.195

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