Scientific Achievement

Observed spin-momentum locked surface states in amorphous Bi2Se3 films, similar to crystalline topological insulator Bi2Se3

Significance and Impact

Represents a milestone toward observing theoretically predicted electronic topological states in amorphous materials with greater flexibility in synthesis for future technological devices

Research Details

  • Synthesized amorphous Bi2Se3 thin films with short-range order similar to topological single crystals
  • Magneto-transport shows increased bulk resistivity compared to crystalline Bi2Se3 and  two-dimensional conductance channels evidenced by weak antilocalization
  • ARPES shows surface states that cross the bulk electronic gap. These states are spin polarized with distinct energy regions of spin polarization seen in SARPES, matching theory using newly developed amorphous topological tight-binding model
  • Synthesized nanocrystalline Bi2Se3 which did NOT show these effects

Publication Details

P. Corbae, S. Ciocys, D. Varjas, E. Kennedy, S. Zeltmann, M. Molina-Ruiz, S. Griffin, C. Jozwiak, Z. Chen, L.-W. Wang, A. M. Minor, M. Scott, A. G. Grushin, A. Lanzara, F. Hellman, Nature Materials (2023).

DOI: 10.1038/s41563-022-01458-0