Quantum transport in zigzag graphene nanoribbon decorated with a phenanthrene molecule

Abstract

By using the first principles calculations which combine density functional theory and nonequilibrium Green's function, we investigate the nanoscopic quantum transport of three hybrid structures consisting of a phenanthrene (PHE) molecule and a zigzag graphene nanoribbon (ZGNR). It is found that after decorated with the PHE molecule, the ZGNRs with the odd (even) zigzag carbon chains show the conductance reduction (enhancement), respectively. With the increase of the number of carbon chains, this odd-even difference will disappear. Moreover, negative differential resistance behavior can also be found in the hybrid structures consisting of the PHE molecule and the antisymmetric ZGNR. Finally, the differential conductance, transmission spectra, and molecular projection self-consistent Hamiltonian are used to explain the physical mechanism clearly. Accordingly, the proposed structures could have broad applications in the design of molecular nanodevices.