Chemical doping and electron-hole conduction asymmetry in graphene devices.
We investigate poly(ethylene imine) and diazonium salts as stable, complementary dopants on graphene. Transport in graphene devices doped with these molecules exhibits asymmetry in electron and hole conductance. The conductance of one carrier is preserved, while the conductance of the other carrier decreases. Simulations based on nonequilibrium Green's function formalism suggest that the origin of this asymmetry is imbalanced carrier injection from the graphene electrodes caused by misalignment of the electrode and channel neutrality points.
Farmer
Damon B
DB
IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA.
Golizadeh-Mojarad
Roksana
R
Perebeinos
Vasili
V
Lin
Yu-Ming
YM
Tulevski
George S
GS
Tsang
James C
JC
Avouris
Phaedon
P
D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D004579:Electron Transport; D006108:Graphite / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
D046911:Macromolecular Substances; D006108:Graphite