Thermopower and resistivity of the topological insulator Bi2Te3 in the amorphous and crystalline phase

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • E. Osmic - , Chair of Physics of High Magnetic Fields, Helmholtz-Zentrum Dresden-Rossendorf, TUD Dresden University of Technology (Author)
  • J. Barzola-Quiquia - , Chemnitz University of Technology, FHR Anlagenbau GmbH (Author)
  • Stephan Winnerl - , Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • W. Böhlmann - , Leipzig University (Author)
  • P. Häussler - , Chemnitz University of Technology (Author)

Abstract

We have, in-situ, prepared and measured the temperature dependence of thermopower S(T) and resistance R(T) of Bi2Te3 topological insulator (TI) thin films in the amorphous and crystalline phase. Samples were prepared by sequential flash-evaporation at liquid 4He temperature. The S(T) in the amorphous phase is negative and much larger compared to other known amorphous materials, while in the crystalline phase it is also negative and behaves linearly with the temperature. The resistivity ρ ( T ) in the amorphous phase shows a semiconducting like behavior that changes to a linear metallic behavior after crystallization. S(T) an ρ ( T ) results in the crystalline phase are in good agreement with results obtained both in bulk and thin films reported in the literature. Linear behavior of the ρ ( T ) for T > 15 K indicates the typical metallic contribution from the surface states as observed in other TI novel materials. The low temperature conductivity T < 10 K exhibits logarithmic temperature dependent positive slope κ ≈ 0.21, indicating the dominance of electron-electron interaction (EEI) over the quantum interference effect, with a clear two dimensional nature of the contribution. Raman spectroscopy showed that the sample has crystallized in the trigonal R 3 ― m space group. Energy-dispersive x-ray spectroscopy reveales high homogeneity in the concentration and no magnetic impurities introduced during preparation or growth.

Details

Original languageEnglish
Article number355001
JournalJournal of Physics Condensed Matter
Volume36
Issue number35
Publication statusPublished - 4 Sept 2024
Peer-reviewedYes

External IDs

PubMed 38804063

Keywords

Keywords

  • amorphous and crystalline topological insulator Bi Te, electron-electron interaction, power factor, Raman spectroscopy, thermopower