Strong Resonances of Quasi 1D Structures at the Bi/InAs(100) Surface

TL;DR

This study investigates the electronic structure of Bi/InAs(100) interfaces, revealing strong one-dimensional resonances of Bi states near the Fermi level influenced by photon energy and polarization, relevant for spintronics and topological insulators.

Contribution

It provides new ARPES data showing how Bi nanolines on InAs(100) create non-dispersive, resonant electronic states with potential implications for spintronic devices.

Findings

Bi states are in the gaps of InAs(100) electronic structure.

Resonant Bi states are nearly non-dispersive perpendicular to nanolines.

Resonance intensity depends on photon energy and polarization.

Abstract

Thin Bi films are interesting candidates for spintronic applications due to a large spin-orbit splitting that, combined with the loss of inversion symmetry at the surface, results in a band structure that is not spin-degenerate. In recent years, applications for topological insulators based on Bi and Bi alloys have as well attracted much attention. Here we present ARPES studies of Bi/InAs(100) interface. Bismuth deposition followed by annealing of the surface results in the formation of one full Bi monolayer decorated by Bi-nanolines. We found that the building up of the interface does affect the electronic structure of the substrate. As a consequence of weak interaction, bismuth states are placed in the gaps of the electronic structure of InAs(100). We observe a strong resonance of the Bi electronic states close to the Fermi level; its intensity depends on the photon energy and the photon polarization. These states show nearly no dispersion when measured perpendicular to the nanolines, confirming their one-dimensionality.