TY - JOUR

T1 - Transport properties of a 1000 nm HgTe film: the interplay of surface and bulk carriers

AU - Savchenko, M L

AU - Kozlov, D A

AU - Vasilev, N N

AU - Mikhailov, N N

AU - Dvoretsky, S A

AU - Kvon, Z D

N1 - Acknowledgment: The work is supported by RFBR Grant No. 18-32-00138. The authors acknowledge TU Wien Bibliothek for financial support through its Open Access Funding Programme. Creative Commons Attribution license.

PY - 2023/5/25

Y1 - 2023/5/25

N2 - We report on systematic study of transport properties of a 1000 nm HgTe film. Unlike thinner and strained HgTe films, which are known as high-quality three-dimensional topological insulators, the film under study is much thicker than the limit of pseudomorphic growth of HgTe on a CdTe substrate. Therefore, the 1000 nm HgTe film is expected to be fully relaxed and has the band structure of bulk HgTe, i.e. a zero gap semiconductor. Additionally, the system is characterized by the bands inversion, so that the two-dimensional topological surface states (TSSs) are expected to exist. To check this claim we studied classical and quantum transport response of the system. We demonstrate that by tuning the top-gate voltage one can change the electron-dominating transport to the hole one. The highest electron mobility is found to be more than300×103 cm2 Vs-1. The system exhibits Shubnikov-de Haas (SdH) oscillations with a complicated pattern and shows up to five independent frequencies in corresponding Fourier spectra. These Fourier peaks are attributed to the TSSs, Volkov-Pankratov states and spin-degenerate bulk states in the accumulation layer near the gate. The observed peculiarities of the quantum transport are the strong SdH oscillations of the Hall resistance, and the suppressed oscillatory response of the TSSs.

AB - We report on systematic study of transport properties of a 1000 nm HgTe film. Unlike thinner and strained HgTe films, which are known as high-quality three-dimensional topological insulators, the film under study is much thicker than the limit of pseudomorphic growth of HgTe on a CdTe substrate. Therefore, the 1000 nm HgTe film is expected to be fully relaxed and has the band structure of bulk HgTe, i.e. a zero gap semiconductor. Additionally, the system is characterized by the bands inversion, so that the two-dimensional topological surface states (TSSs) are expected to exist. To check this claim we studied classical and quantum transport response of the system. We demonstrate that by tuning the top-gate voltage one can change the electron-dominating transport to the hole one. The highest electron mobility is found to be more than300×103 cm2 Vs-1. The system exhibits Shubnikov-de Haas (SdH) oscillations with a complicated pattern and shows up to five independent frequencies in corresponding Fourier spectra. These Fourier peaks are attributed to the TSSs, Volkov-Pankratov states and spin-degenerate bulk states in the accumulation layer near the gate. The observed peculiarities of the quantum transport are the strong SdH oscillations of the Hall resistance, and the suppressed oscillatory response of the TSSs.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85160204064&origin=inward&txGid=43d40646f0a7c996c2e1469375dd3526

UR - https://www.mendeley.com/catalogue/f69a976d-a2f9-328f-89de-e10291e0a45b/

U2 - 10.1088/1361-648X/acd5a2

DO - 10.1088/1361-648X/acd5a2

M3 - Article

C2 - 37187189

VL - 35

JO - Journal of Physics Condensed Matter

JF - Journal of Physics Condensed Matter

SN - 0953-8984

M1 - 345302

ER -