title: Observation of unconventional quantum spin textures in topological insulators.
abstract: A topologically ordered material is characterized by a rare quantum organization of electrons that evades the conventional spontaneously broken symmetry-based classification of condensed matter. Exotic spin-transport phenomena, such as the dissipationless quantum spin Hall effect, have been speculated to originate from a topological order whose identification requires a spin-sensitive measurement, which does not exist to this date in any system. Using Mott polarimetry, we probed the spin degrees of freedom and demonstrated that topological quantum numbers are completely determined from spin texture-imaging measurements. Applying this method to Sb and Bi(1-x)Sb(x), we identified the origin of its topological order and unusual chiral properties. These results taken together constitute the first observation of surface electrons collectively carrying a topological quantum Berry's phase and definite spin chirality, which are the key electronic properties component for realizing topological quantum computing bits with intrinsic spin Hall-like topological phenomena.
authors.affiliation: Joseph Henry Laboratories of Physics, Department of Physics, Princeton University, Princeton, NJ 08544, USA.
authors.forename: D
authors.initials: D
authors.lastname: Hsieh
authors.forename: Y
authors.initials: Y
authors.lastname: Xia
authors.forename: L
authors.initials: L
authors.lastname: Wray
authors.forename: D
authors.initials: D
authors.lastname: Qian
authors.forename: A
authors.initials: A
authors.lastname: Pal
authors.forename: J H
authors.initials: JH
authors.lastname: Dil
authors.forename: J
authors.initials: J
authors.lastname: Osterwalder
authors.forename: F
authors.initials: F
authors.lastname: Meier
authors.forename: G
authors.initials: G
authors.lastname: Bihlmayer
authors.forename: C L
authors.initials: CL
authors.lastname: Kane
authors.forename: Y S
authors.initials: YS
authors.lastname: Hor
authors.forename: R J
authors.initials: RJ
authors.lastname: Cava
authors.forename: M Z
authors.initials: MZ
authors.lastname: Hasan