Experimental Realization of Spin-Polarized States on Mg3Bi2 Surface

Kagome compound Mg3Bi2 is theoretically predicted to be a nodal line semimetal while the inclusion of spin-orbit coupling (SOC) causes a transition to strong topological insulator. The electronic energy dispersion and spin polarization of thus attained surface states are sensitive to the surface terminations, which are not experimentally verified yet. Herein, the major Mg terminations with scanning tunneling microscopy (STM) are identified and the electronic structures near and above the Fermi level are further investigated. It is found that the underlying Bi layers contribute to the surface states dominantly. The spin-polarized bulk and surface states may promote low-dissipation applications for Mg3Bi2.

Automated summary

The study reveals that Mg3Bi2 compound has unique surface states and spin polarization, dominated by the underlying Bi layers, which may provide opportunities for low-dissipation applications.