Eur. Phys. J. B (2021) 94: 75
https://doi.org/10.1140/epjb/s10051-021-00072-4

Regular Article - Mesoscopic and Nanoscale Systems

Electronic properties of graphene quantum ring with wedge disclination

¹ Laboratory of Theoretical Physics, Faculty of Sciences, Chouaïb Doukkali University, PO Box 20, 24000, El Jadida, Morocco
² Canadian Quantum Research Center, 204-3002 32 Ave, V1T 2L7, Vernon, BC, Canada
³ Physics Department, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Saudi Arabia

^b ahmed.jellal@gmail.com, a.jellal@ucd.ac.ma

Received: 5 October 2020
Accepted: 24 February 2021
Published online: 29 March 2021

Abstract

We study the energy spectrum and persistent current of charge carriers confined in a graphene quantum ring geometry of radius R and width w subject to a magnetic flux. We consider the case where the crystal symmetry is locally modified through dislocations created by replacing the original carbon hexagon by a pentagon, square, heptagon or octagon. To model this type of defect, we include appropriate boundary conditions for the angular coordinate. The electrons are then confined to a finite width strip in the radial direction by setting an infinite mass boundary conditions at the edges of the strip. The solutions are expressed in terms of Hankel functions and their asymptotic behavior allows to derive quantized energy levels in the presence of an energy gap. We also investigate the persistent currents that appear in the quantum ring in the presence of a quantum flux at the center of the ring and how wedge disclination influences different quantum transport quantities.