Nitrogen-intercalated twisted bilayer graphene nanoribbons: Electronic, magnetic, and transport properties

Abstract

Layer twisting in graphenelike materials enables novel physical properties through an additional degree of freedom. Here, we investigate the electronic, magnetic, and thermoelectric properties of antiferromagnetic twisted bilayer graphene nanoribbons using first-principles calculations combined with the coherent transport formalism. Both armchair- and zigzag-edge configurations were examined at four representative twist angles (α = 0◦,13.17◦, 9.43◦, 7.34◦) to explore the interplay between moiré-induced electronic reconstruction and interlayer nitrogen (N) intercalation. The results show that intercalated N atoms modify interlayer coupling and induce spin splitting in the band structure, leading to spin-dependent transport phenomena. Tuning the twist angle drives transitions among metallic, half-metallic, and spin-semiconducting states, accompanied by localized band-edge features at smaller α. These tunable electronic and magnetic properties yield large spin-Seebeck coefficients and spin currents under thermal gradients and bias voltage. The combined effects of N-intercalated and twist modulation offer an efficient route to control spin-polarized transport and energy conversion in bilayer graphene nanostructures.