The interplay between the Aharonov-Bohm interference and parity selective tunneling in graphene nanoribbon rings.
We report on a numerical study of the Aharonov-Bohm (AB) effect and parity selective tunneling in pn junctions based on rectangular graphene rings where the contacts and ring arms are all made of zigzag nanoribbons. We find that when applying a magnetic field to the ring, the AB interference can reverse the parity symmetry of incoming waves and hence can strongly modulate the parity selective transmission through the system. Therefore, the transmission between two states of different parity exhibits the AB oscillations with a π-phase shift, compared to the case of states of the same parity. On this basis, it is shown that interesting effects, such as giant (both positive and negative) magnetoresistance and strong negative differential conductance, can be achieved in this structure. Our study thus presents a new property of the AB interference in graphene nanorings, which could be helpful for further understanding the transport properties of graphene mesoscopic systems.
L-Sim, SP2M, UMR-E CEA/UJF-Grenoble 1, INAC, 38054 Grenoble, France. Center for Computational Physics, Institute of Physics, Vietnam Academy of Science and Technology, PO Box 429 Bo Ho, 10000 Hanoi, Vietnam.
V Hung
VH
Nguyen
Y-M
YM
Niquet
P
P
Dollfus
D003198:Computer Simulation; D004553:Electric Conductivity; D006108:Graphite / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D012666:Semiconductors
D006108:Graphite