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Fermi level tuning of Ag-doped Bi₂Se₃ topological insulator.

ABSTRACT: The temperature dependence of the resistivity (ρ) of Ag-doped Bi₂Se₃ (Ag_xBi_2-xSe₃) shows insulating behavior above 35 K, but below 35 K, ρ suddenly decreases with decreasing temperature, in contrast to the metallic behavior for non-doped Bi₂Se₃ at 1.5-300 K. This significant change in transport properties from metallic behavior clearly shows that the Ag doping of Bi₂Se₃ can effectively tune the Fermi level downward. The Hall effect measurement shows that carrier is still electron in Ag_xBi_2-xSe₃ and the electron density changes with temperature to reasonably explain the transport properties. Furthermore, the positive gating of Ag_xBi_2-xSe₃ provides metallic behavior that is similar to that of non-doped Bi₂Se₃, indicating a successful upward tuning of the Fermi level.

SUBMITTER: Uesugi E

PROVIDER: S-EPMC6440949 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Fermi level tuning of Ag-doped Bi2Se3 topological insulator.

Uesugi Eri E Uchiyama Takaki T Goto Hidenori H Ota Hiromi H Ueno Teppei T Fujiwara Hirokazu H Terashima Kensei K Yokoya Takayoshi T Matsui Fumihiko F Akimitsu Jun J Kobayashi Kaya K Kubozono Yoshihiro Y

Scientific reports 20190329 1

The temperature dependence of the resistivity (ρ) of Ag-doped Bi2Se3 (AgxBi2-xSe3) shows insulating behavior above 35 K, but below 35 K, ρ suddenly decreases with decreasing temperature, in contrast to the metallic behavior for non-doped Bi2Se3 at 1.5-300 K. This significant change in transport properties from metallic behavior clearly shows that the Ag doping of Bi2Se3 can effectively tune the Fer ...[more]

PMID: 30926890

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