Paper

Orbital Complexity in Intrinsic Magnetic Topological Insulators MnBi\\(_4\\)Te\\(_7\\) and MnBi\\(_6\\)Te\\(_{10}\\)

Shimada, K, Figgemeier, T, Cacho, C, Schwier, E F, nari, C I, Reinert, F, Jung, S, Vidal, R C, Büchner, B, Heider, T, Plucinski, L, Peixoto, T R F, van den Brink, J, Schneider, C M, Isaeva, A, Bentmann, H, Facio, J I, Kagerer, P, Richter, M

2021

Overview

Using angle-resolved photoelectron spectroscopy (ARPES), we investigate the surface electronic structure of the magnetic van der Waals compounds MnBi\\(_4\\)Te\\(_7\\) and MnBi\\(_6\\)Te\\(_{10}\\), the \\(n=\\)~1 and 2 members of a modular (Bi\\(_2\\)Te\\(_3\\))\\(_n\\)(MnBi\\(_2\\)Te\\(_4\\)) series, which have attracted recent interest as intrinsic magnetic topological insulators. Combining circular dichroic, spin-resolved and photon-energy-dependent ARPES measurements with calculations based on density functional theory, we unveil complex momentum-dependent orbital and spin textures in the surface electronic structure and disentangle topological from trivial surface bands. We find that the Dirac-cone dispersion of the topologial surface state is strongly perturbed by hybridization with valence-band states for Bi\\(_2\\)Te\\(_3\\)-terminated surfaces but remains preserved for MnBi\\(_2\\)Te\\(_4\\)-terminated surfaces. Our results firmly establish the topologically non-trivial nature of these magnetic van der Waals materials and indicate that the possibility of realizing a quantized anomalous Hall conductivity depends on surface termination.

• Publisher: Cornell University Library, arXiv.org
• Subject: Angular momentum / Band theory / Complexity / Density functional theory / Dichroism / Electronic structure / Electrons / Photoelectrons / Surface layers / Topological insulators / Topology