Anomalous Landau quantization in intrinsic magnetic topological insulators
Abstract
The intrinsic magnetic topological insulator, Mn(Bi1−xSbx)2Te4, has been identified as a Weyl semimetal with a single pair of Weyl nodes in its spin-aligned strong-field configuration. A direct consequence of the Weyl state is the layer dependent Chern number, $$C$$ C . Previous reports in MnBi2Te4 thin films have shown higher $$C$$ C states either by increasing the film thickness or controlling the chemical potential. A clear picture of the higher Chern states is still lacking as data interpretation is further complicated by the emergence of surface-band Landau levels under magnetic fields. Here, we report a tunable layer-dependent $$C$$ C = 1 state with Sb substitution by performing a detailed analysis of the quantization states in Mn(Bi1−xSbx)2Te4 dual-gated devices—consistent with calculations of the bulk Weyl point separation in the doped thin films. The observed Hall quantization plateaus for our thicker Mn(Bi1−xSbx)2Te4 films under strong magnetic fields can be interpreted by a theory of surface and bulk spin-polarised Landau level spectra in thin film magnetic topological insulators.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 09, 2023
- Source ID
- 10.1038/s41467-023-40383-x
Entities
People
- Allan H. MacDonald
- Chao Lei
- J. Jaroszyński
- Kang L. Wang
- Seng Huat Lee
- Su Kong Chong
- Zhiqiang Mao
Organizations
- Army Research Office
- National Science Foundation