Controlling the layer localization of gapless states in bilayer graphene with a gate voltage
Year: 2018
Type: article
Abstract: Experiments in gated bilayer graphene with stacking domain walls present topological gapless states protected by no-valley mixing. Here we research these states under gate voltages using atomistic models, which allow us to elucidate their origin. We find that the gate potential controls the layer localization of the two states, which switches non-trivially between layers depending on the applied gate voltage magnitude. We also show how these bilayer gapless states arise from bands of single-layer graphene by analyzing the formation of carbon bonds between layers. Based on this analysis we provide a model Hamiltonian with analytical solutions, which explains the layer localization as a function of the ratio between the applied potential and interlayer hopping. Our results open a route for the manipulation of gapless states in electronic devices, analogous to the proposed writing and reading memories in topological insulators.
Source: 2D Materials
Authors: W Jaskólski, M Pelc, Garnett W Bryant, Leonor Chico, A Ayuela
Institutions: Nicolaus Copernicus University, Material Physics Center, Donostia International Physics Center, National Institute of Standards and Technology, Joint Quantum Institute, Consejo Superior de Investigaciones Científicas, Instituto de Ciencia de Materiales de Madrid, University of the Basque Country
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,895
OpenAlex ID: W2760722315