Mn-Rich MnSb2 Te4 A Topological Insulator with Magnetic Gap Closing at High Curie Temperatures of 45-50 K

Mn-Rich MnSb2 Te4 : A Topological Insulator with Magnetic Gap Closing at High Curie Temperatures of 45-50 K

© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 42 vom: 27. Okt., Seite e2102935
1. Verfasser: Wimmer, Stefan (VerfasserIn)
Weitere Verfasser: Sánchez-Barriga, Jaime, Küppers, Philipp, Ney, Andreas, Schierle, Enrico, Freyse, Friedrich, Caha, Ondrej, Michalička, Jan, Liebmann, Marcus, Primetzhofer, Daniel, Hoffman, Martin, Ernst, Arthur, Otrokov, Mikhail M, Bihlmayer, Gustav, Weschke, Eugen, Lake, Bella, Chulkov, Evgueni V, Morgenstern, Markus, Bauer, Günther, Springholz, Gunther, Rader, Oliver
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article Mn-Sb site exchange MnSb2Te4 magnetic bandgap magnetic topological insulators magnetization molecular beam epitaxy
Beschreibung
Zusammenfassung:© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.
Ferromagnetic topological insulators exhibit the quantum anomalous Hall effect, which is potentially useful for high-precision metrology, edge channel spintronics, and topological qubits.  The stable 2+ state of Mn enables intrinsic magnetic topological insulators. MnBi2 Te4 is, however, antiferromagnetic with 25 K Néel temperature and is strongly n-doped. In this work, p-type MnSb2 Te4 , previously considered topologically trivial, is shown to be a ferromagnetic topological insulator for a few percent Mn excess. i) Ferromagnetic hysteresis with record Curie temperature of 45-50 K, ii) out-of-plane magnetic anisotropy, iii) a 2D Dirac cone with the Dirac point close to the Fermi level, iv) out-of-plane spin polarization as revealed by photoelectron spectroscopy, and v) a magnetically induced bandgap closing at the Curie temperature, demonstrated by scanning tunneling spectroscopy (STS), are shown. Moreover, a critical exponent of the magnetization β ≈ 1 is found, indicating the vicinity of a quantum critical point. Ab initio calculations reveal that Mn-Sb site exchange provides the ferromagnetic interlayer coupling and the slight excess of Mn nearly doubles the Curie temperature. Remaining deviations from the ferromagnetic order open the inverted bulk bandgap and render MnSb2 Te4 a robust topological insulator and new benchmark for magnetic topological insulators
Beschreibung:Date Revised 13.10.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202102935