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セガワ コウジ
SEGAWA KOJI
瀬川 耕司 所属 京都産業大学 理学部 物理科学科 職種 教授 |
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| 言語種別 | 英語 |
| 発行・発表の年月 | 2015/04 |
| 形態種別 | 研究論文 |
| 標題 | Dual-Gated Topological Insulator Thin-Film Device for Efficient Fermi-Level Tuning |
| 執筆形態 | その他 |
| 掲載誌名 | ACS NANO |
| 出版社・発行元 | AMER CHEMICAL SOC |
| 巻・号・頁 | 9(4),pp.4050-4055 |
| 著者・共著者 | Fan Yang,A. A. Taskin,Satoshi Sasaki,Kouji Segawa,Yasuhide Ohno,Kazuhiko Matsumoto,Yoichi Ando |
| 概要 | Observations of novel quantum phenomena expected for three-dimensional topological insulators (TIs) often require fabrications of thin-film devices and tuning of the Fermi level across the Dirac point. Since thin films have both top and bottom surfaces, an effective control of the surface chemical potential requires dual gating. However, a reliable dual-gating technique for TI thin films has not yet been developed. Here we report a comprehensive method to fabricate a dual-gated TI device and demonstrate tuning of the chemical potential of both surfaces across the Dirac points. The most important part of our method is the recipe for safely detaching high-quality, bulk-insulating (Bi1-xSbx)(2)Te-3 thin films from sapphire substrates and transferring them to Si/SiO2 wafers that allow back gating. Fabrication of an efficient top gate by low-temperature deposition of a SiNx dielectric complements the procedure. Our dual-gated devices are shown to be effective in tuning the chemical potential in a wide range encompassing the Dirac points on both surfaces. |
| DOI | 10.1021/acsnano.5b00102 |
| ISSN | 1936-0851/1936-086X |
| PermalinkURL | https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84928782697&origin=inward |