2024-03-29T14:40:30Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1608562020-05-29T07:55:58Zcom_10261_115com_10261_3com_10261_31col_10261_494col_10261_410
00925njm 22002777a 4500
dc
Lobo-Checa, Jorge
author
Schiller, Frederik
author
Corso, Martina
author
Miccio, Luis A.
author
Piquero-Zulaica, Ignacio
author
Ortega, J. Enrique
author
2016
Bismuth is a semimetal whose surface shows better metal behaviour than its bulk counterpart due to the presence of metallic-like surface states. These are spin-split given its large atomic weight and spin orbit interaction. Depending on the crystal termination these states behave as two dimensional (2D), delocalized states, or one dimensional (1D), localized states. Such modification of the electron wavefunction is induced by the presence of step arrays, by repulsive scattering at steps and confinement within terraces and has been widely explored for Shockley states in noble metals. Semimetals have not received such a widespread attention but the investigating of this 2D to 1D transition is particularly interesting since Bi is very close to being a topological insulator and great interest has emerged in topologically guaranteed 1D surface states. We present a study that finely explores the 2D-1D transition in Bismuth surface states using a curved crystal. Such special samples allows for a smooth
variation of the surface orientation, which translates into a smooth variation of the step
separation, i.e. the step potential barriers. The evolution of the electronic structure is
investigated by state-of-the-art ARPES and correlated to the local structure obtained from STM and LEED. We find that unreconstructed single bilayer height terraces stabilize these one-dimensional states. Moreover, we observed the existence of coherent 1D edge states which are delocalized across the terrace length in spite of the absence of topological protection. They hold similar characteristics of quantum spin hall states and can help realizing electronic transport via edge channels, essential for future spintronic devices.
Fuerzas y TĂșnel (2016)
http://hdl.handle.net/10261/160856
Surface dimensionality transition on a curved Bi(111) sample