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Updated: Jun 26, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Chemical doping and electron-hole conduction asymmetry in graphene devices
Damon B Farmer1, Roksana Golizadeh-Mojarad, Vasili Perebeinos
1IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA.
Abstract:
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.
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