文摘
We report a direct observation of surface dominated conduction in an intrinsic Bi2Se3 thin film with a thickness of six quintuple layers grown on lattice-matched CdS (0001) substrates by molecular beam epitaxy. Shubnikov-de Haas oscillations from the topological surface states suggest that the Fermi level falls inside the bulk band gap and is 53 卤 5 meV above the Dirac point, which is in agreement with 70 卤 20 meV obtained from scanning tunneling spectroscopies. Our results demonstrate a great potential of producing genuine topological insulator devices using Dirac Fermions of the surface states, when the film thickness is pushed to nanometer range.
Keywords:
Intrinsic topological insulator; Bi2Se3; transport properties; surface states; quantum oscillations