Chemical Aspects of the Candidate Antiferromagnetic Topological Insulator $MnBi_{2}Te_{4}$
| Autor: | Hendrik Bentmann, Raphael C. Vidal, Simon Moser, Thomas Doert, Martin Kaiser, K. Kißner, Friedrich Reinert, Bernd Rellinghaus, S. Gaß, Oliver Oeckler, Alexander Zeugner, Chul Hee Min, Francesco Scaravaggi, Richard Hentrich, M. Ünzelmann, Michael Ruck, Kornelius Nielsch, Celso I. Fornari, S. Schatz, Thiago R. F. Peixoto, Anna Isaeva, Bernd Büchner, Darius Pohl, Frederik Nietschke, Christian Hess, Anja U. B. Wolter, Axel Lubk, Christine Damm |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Materials science
Condensed matter physics General Chemical Engineering Slow cooling 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Topological insulator ddc:540 Materials Chemistry Melting point Narrow range Antiferromagnetism 0210 nano-technology |
| Zdroj: | Chemistry of materials 31(8), 2795-2806 (2019). doi:10.1021/acs.chemmater.8b05017 |
| DOI: | 10.3204/pubdb-2021-02700 |
| Popis: | Chemistry of materials 31(8), 2795 - 2806 (2019). doi:10.1021/acs.chemmater.8b05017 High-quality single crystals of MnBi2Te4 are grown for the first time by slow cooling within a narrow range between the melting points of Bi$_2$Te$_3$ (586 °C) and MnBi$_2$Te$_4$ (600 °C). Single-crystal X-ray diffraction and electron microscopy reveal ubiquitous antisite defects in both cation sites and, possibly, Mn vacancies (Mn$_{0.85(3)}$Bi$_{2.10(3)}$Te$_4$). Thermochemical studies complemented with high-temperature X-ray diffraction establish a limited high-temperature range of phase stability and metastability at room temperature. Nevertheless, the synthesis of MnBi$_2$Te$_4$ can be scaled-up as powders can be obtained at subsolidus temperatures and quenched at room temperature. Bulk samples exhibit long-range antiferromagnetic ordering below 24 K. The Mn(II) out-of-plane magnetic state is confirmed by the magnetization, X-ray photoemission, X-ray absorption, and linear dichroism measurements. The compound shows a metallic type of resistivity in the range 4.5–300 K and is an n-type conductor that reaches a thermoelectric figure of merit up to ZT = 0.17. Angle-resolved photoemission experiments show a surface state forming a gapped Dirac cone, thus strengthening MnBi$_2$Te$_4$ as a promising candidate for the intrinsic magnetic topological insulator, in accordance with theoretical predictions. The developed synthetic protocols enable further experimental studies of a crossover between magnetic ordering and nontrivial topology in bulk MnBi$_2$Te$_4$. Published by American Chemical Society, Washington, DC |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|