Observation of spin polarized surface states in polar Weyl semimetal MoTe2

Since the theoretical prediction of the low temperature phase as a type-II Weyl semimetal, the electronic structure of β-MoTe₂ has been actively studied by angle-resolved photoelectron spectroscopy. Until now, some segment-like band features resembling Fermi arcs are experimentally observed, which are indicative of the topological surface states connecting the bulk Weyl nodes. However, the band dispersions near the Fermi level is complicated, and clear interpretation is not easy. Here we investigate the spin polarizations of the Fermi arc features for both polar terminations by utilizing the high-resolution spin and angle-resolved photoelectron spectroscopy (SARPES). For respective surface terminations, the different patterns and spin polarizations of Fermi arcs are clearly observed. In the presentation, we will compare the result with the first-principles calculation and discuss the details of the spin polarized surface states.