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arXiv · 2409.19666

Surface structure of the 3x3-Si phase on Al(111), studied by the multiple usages of positron diffraction and core-level photoemission spectroscopy

Yusuke Sato·Yuki Fukaya·Akito Nakano·Takeo Hoshi·Chi-Cheng Lee·Kazuyoshi Yoshimi·Taisuke Ozaki·Takeru Nakashima·Yasunobu Ando·Hiroaki Aoyama·Tadashi Abukawa·Yuki Tsujikawa·Masafumi Horio·Masahito Niibe·Fumio Komori·Iwao Matsuda
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Abstract

The structure of an Al(111)3x3-Si surface was examined by combining data from positron diffraction and core-level photoemission spectroscopy. Analysis of the diffraction rocking curves indicated that the overlayer had a flat honeycomb lattice structure. Simulations of Si core-level spectra calculated via the first-principles indicated that one of the Si atoms in the unit cell was replaced by an Al atom. The surface superstructure was thus a two-dimensional layer of Al-embedded silicene on Al(111).

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Yusuke Sato, Yuki Fukaya, Akito Nakano, Takeo Hoshi, Chi-Cheng Lee, Kazuyoshi Yoshimi, Taisuke Ozaki, Takeru Nakashima, Yasunobu Ando, Hiroaki Aoyama, Tadashi Abukawa, Yuki Tsujikawa, Masafumi Horio, Masahito Niibe, Fumio Komori, Iwao Matsuda. 2024-09-29. Surface structure of the 3x3-Si phase on Al(111), studied by the multiple usages of positron diffraction and core-level photoemission spectroscopy. https://arxiv.org/abs/2409.19666

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