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arXiv · 1308.5521

Realization of bulk insulating property and carrier manipulation in reversible spin current regime of the ideal topological insulator TlBiSe2

Kenta Kuroda·Gaku Eguchi·Kaito Shirai·Masashi Shiraishi·Mao Ye·Koji Miyamoto·Taichi Okuda·Shigenori Ueda·Masashi Arita·Hirofumi Namatame·Masaki Taniguchi·Yoshifumi Ueda·Akio Kimura
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Abstract

The surfaces of three-dimensional topological insulators (TIs) characterized by a spin-helical Dirac fermion provide a fertile ground for realizing exotic phenomena as well as having potential for wide-ranging applications. To realize most of their special properties, the Dirac point (DP) is required to be located near the Fermi energy with a bulk insulating property while it is hardly achieved in most of the discovered TIs. It has been recently found that TlBiSe2 features an in-gap DP, where upper and lower parts of surface Dirac cone are both utilized. Nevertheless, investigations of the surface transport properties of this material are limited due to the lack of bulk insulating characteristics. Here, we present the first realization of bulk insulating property by tuning the composition of Tl1-xBi1+xSe2-d without introducing guest atoms that can bring the novel properties into the reality. This result promises to shed light on new exotic topological phenomena on the surface.

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Kenta Kuroda, Gaku Eguchi, Kaito Shirai, Masashi Shiraishi, Mao Ye, Koji Miyamoto, Taichi Okuda, Shigenori Ueda, Masashi Arita, Hirofumi Namatame, Masaki Taniguchi, Yoshifumi Ueda, Akio Kimura. 2014-05-30. Realization of bulk insulating property and carrier manipulation in reversible spin current regime of the ideal topological insulator TlBiSe2. https://doi.org/10.1103/physrevb.91.205306

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