title: Effective Hamiltonian for surface states of topological insulator nanotubes.
abstract: In this work we derive an effective Hamiltonian for the surface states of a hollow topological insulator (TI) nanotube with finite width walls. Unlike a solid TI cylinder, a TI nanotube possesses both an inner as well as outer surface on which the states localized at each surface are coupled together. The curvature along the circumference of the nanotube leads to a spatial variation of the spin orbit interaction field experienced by the charge carriers as well as an asymmetry between the inner and outer surfaces of the nanotube. Both of these features result in terms in the effective Hamiltonian for a TI nanotube absent in that of a flat TI thin film of the same thickness. We calculate the numerical values of the parameters for a Bi2Se3nanotube as a function of the inner and outer radius, and show that the differing relative magnitudes between the parameters result in qualitatively differing behaviour for the eigenstates of tubes of different dimensions.
authors.affiliation: Computational Nanoelectronics and Nanodevices Laboratory, National University of Singapore, Singapore, Singapore.
authors.forename: Zhuo Bin
authors.initials: ZB
authors.lastname: Siu
authors.affiliation: Computational Nanoelectronics and Nanodevices Laboratory, National University of Singapore, Singapore, Singapore.|Data Storage Institute, Agency for Science, Reseach and Technology, Singapore.
authors.forename: Seng Ghee
authors.initials: SG
authors.lastname: Tan
authors.affiliation: Computational Nanoelectronics and Nanodevices Laboratory, National University of Singapore, Singapore, Singapore.|Computational Nanoelectronics and Nanodevices Laboratory, National University of Singapore, Singapore, Singapore.
authors.forename: Mansoor B A
authors.initials: MB
authors.lastname: Jalil