title: Observation of Zeeman effect in topological surface state with distinct material dependence.
abstract: Manipulating the spins of the topological surface states represents an essential step towards exploring the exotic quantum states emerging from the time reversal symmetry breaking via magnetic doping or external magnetic fields. The latter case relies on the Zeeman effect and thereby we need to estimate the g-factor of the topological surface state precisely. Here, we report the direct observations of the Zeeman effect at the surfaces of Bi2Se3 and Sb2Te2Se by spectroscopic-imaging scanning tunnelling microscopy. The Zeeman shift of the zero mode Landau level is identified unambiguously by appropriately excluding the extrinsic effects arising from the nonlinearity in the band dispersion of the topological surface state and the spatially varying potential. Surprisingly, the g-factors of the topological surface states in Bi2Se3 and Sb2Te2Se are very different (+18 and -6, respectively). Such remarkable material dependence opens up a new route to control the spins of the topological surface states.
authors.affiliation: School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China.|RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan.
authors.forename: Ying-Shuang
authors.initials: YS
authors.lastname: Fu
authors.affiliation: RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hanaguri
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Igarashi
authors.affiliation: RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kawamura
authors.affiliation: RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan.|Department of Applied Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: M S
authors.initials: MS
authors.lastname: Bahramy
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sasagawa