Topological insulator ribbon: Surface states and dynamical response

Abstract

We study theoretically the distributions of charge and spin polarization of a topological insulator ribbon, with a realistic rectangular cross section. Due to constriction in two lateral directions, the surface states discretize into a series of subbands inside of the bulk band gap. The charge and spin distribution show interesting characters which are different from an ideal topological surface state. The effect of merging of four different surface states into the new one as an entity are analyzed. Optical conductivity and dynamical spin susceptibility of the ribbon are studied. Different from a single ideal surface, the optical response and dynamical spin susceptibility of a ribbon do not have a clear correspondence. The dynamical spin susceptibility could be used to identify the more adequate model for Bi${}_2$Se${}_3$.

6 pages, 4 figures, references updated

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Cited by in corpus (6)

• The Josephson current in Fe-based superconducting junctions: theory and experiment
• Confinement and Fermion Doubling Problem in Dirac-like Hamiltonians
• Surface states and local spin susceptibility in doped three-dimensional topological insulators with odd-parity superconducting pairing symmetry
• Inelastic magnetic scattering effect on LDOS of topological insulators
• Unusual spin dynamics in topological insulators
• Non-unique connection between bulk topological invariants and surface physics