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arXiv · 1406.2048

Controlling the 2DEG states evolution at a metal/Bi$_2$Se$_3$ interface

Han-Jin Noh·Jinwon Jeong·En-Jin Cho·Joonbum Park·Jun Sung Kim·Ilyou Kim·Byeong-Gyu Park·Hyeong-Do Kim
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Abstract

We have demonstrated that the evolution of the two-dimensional electron gas (2DEG) system at an interface of metal and the model topological insulator (TI) Bi$_2$Se$_3$ can be controlled by choosing an appropriate kind of metal elements and by applying a low temperature evaporation procedure. In particular, we have found that only topological surface states (TSSs) can exist at a Mn/Bi$_2$Se$_3$ interface, which would be useful for implementing an electric contact with surface current channels only. The existence of the TSSs alone at the interface was confirmed by angle-resolved photoemission spectroscopy (ARPES). Based on the ARPES and core-level x-ray photoemission spectroscopy measurements, we propose a cation intercalation model to explain our findings.

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Han-Jin Noh, Jinwon Jeong, En-Jin Cho, Joonbum Park, Jun Sung Kim, Ilyou Kim, Byeong-Gyu Park, Hyeong-Do Kim. 2014-06-09. Controlling the 2DEG states evolution at a metal/Bi$_2$Se$_3$ interface. https://doi.org/10.1103/physrevb.91.121110

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