Multiple surface resonance electronic spin states in the strong topological metal Zr2Te2P

Abstract

Nonzero spin polarization occurs in nonmagnetic materials induced by spin-orbital coupling when inversion symmetry is broken. Understanding the origin of spin polarization is essential for finding effective methods of manipulating the electron spin. Recently, nontrivial Dirac node arcs with a novel spin texture have been reported in a tetradymite family ${M}_{2}{\text{Te}}_{2}X$ (with $M=\text{Ti}$, Zr, or Hf and $X=\text{P}$ or As) and have potential applications in spintronics. Here, combining spin- and angle-resolved photoemission spectroscopy and first-principles calculations, we have unambiguously distinguished the spin-polarized topological surface states from the bulk continuum states in ${\text{Zr}}_{2}{\text{Te}}_{2}\text{P}$, and report that surface resonance Rashba-type spin splittings and spin-momentum-layer locked bulk states exist along with the Dirac node arcs in reciprocal space in adjacent energy ranges. Our work shows the importance of resonance and hybridization between surface and bulk states to their electronic spin textures and provides a platform for developing spintronics devices.