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arXiv · 2205.05259

Electronic topological transition of 2D boron by the ion exchange reaction

Xiaoni Zhang·Yuki Tsujikawa·Ikuma Tateishi·Masahito Niibe·Tetsuya Wada·Masafumi Horio·Miwa Hikichi·Yasunobu Ando·Kunio Yubuta·Takahiro Kondo·Iwao Matsuda
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Abstract

We systematically investigated electronic evolutions of non-symmorphic borophene with chemical environments that were realized by the ion exchange method. Electronic structures can be characterized by the topological $Z_2$ invariant. Spectroscopic experiments and DFT calculations unveiled that a sheet of hydrogenated borophene (borophane) is the Dirac nodal loop semimetal ($Z_2=-1$), while a layered crystal of YCrB$_4$ is an insulator ($Z_2=1$). The results demonstrate the electronic topological transition by replacement of the counter atoms on the non-symmorphic borophene layer.

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Xiaoni Zhang, Yuki Tsujikawa, Ikuma Tateishi, Masahito Niibe, Tetsuya Wada, Masafumi Horio, Miwa Hikichi, Yasunobu Ando, Kunio Yubuta, Takahiro Kondo, Iwao Matsuda. 2022-05-11. Electronic topological transition of 2D boron by the ion exchange reaction. https://arxiv.org/abs/2205.05259

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