Potential spin-polarized transport in gold-doped armchair graphene nanoribbons

• Edge Au-substitution promotes semiconductor–metal transition in AGNR.
• NDR due to bias-dependent transmission in Au-substituted AGNRs.
• Voltage controlled spin injection in all investigated Au-doped AGNRs.
• Strong spin polarization occurs at 0.5 V in Au-hole adsorbed AGNRs.

Based on NEGF-DFT computations, systematic investigation of electronic, magnetic and transport properties of AGNRs are done by employing Au through different doping mechanisms. Remarkable Au–AGNR bonding is observed in case of substitution due to the presence of impurity at the edges. Both substitution and adsorption of Au on AGNR surface induce significant changes in the electronic spin transport of the sp2 hybridized carbon sheets. AGNRs are semiconducting with lower total energy for the FM configuration, and the I–V characteristics reveal semiconductor to metal transition of Au-doped AGNR. The spin injection is voltage controlled in all the investigated Au-doped AGNRs.