Cai, Y.; Zhang, J.; Zha, H.; Zhang, F.; Wang, Y.; Chen, W.; Hao, Z.; Deng, L.; Liu, W.; Rong, H.; Jiang, Z.; Yang, Y.; Jiang, Q.; Liu, Z.; Ye, M.; Rienks, E.D.L.; Huang, Y.; Guo, S.; Lin, J.; Wang, L.; Qihang, L.; Shan, Q.; Chen, C: Observation of Highly Spin-Polarized Dangling Bond Surface States in Rare-Earth Pnictide Tellurides. Advanced Materials 37 (2025), p. 2411733/1-8
10.1002/adma.202411733
Abstract:
To generate and manipulate spin-polarized electronic states in solids are crucial for modern spintronics. The textbook routes employ quantum well states or Shockley/topological type surface states whose spin degeneracy is lifted by strong spin-orbit coupling and inversion symmetry breaking at the surface/interface. The resultant spin polarization is usually truncated because of the intertwining between multiple orbitals. Here a unique type of surface states is realized, namely, dangling bond surface states in a family of ternary rare-earth pnictide tellurides RePnTe (Re = La, Gd, Ce; Pn = Sb, Bi), with robust band structure and sizeable spin splitting. Spin and angle-resolved photoemission spectroscopy measurements reveal high spin polarization and distinct spin-momentum locking texture, which, according to the theoretical analysis, arise from local site asymmetry and surface-purified spin-orbital texture. The work extends the so-called “hidden spin polarization” from the bulk to the surface, presenting an intriguing spin-orbital-momentum-layer locking phenomenon, which may shed lights on potential spintronic applications.