Manipulation the Transportation Properties of Benzene Molecules via the Connected Transition Metal Atoms

Abstract

The first principles based on density functional theory and non-equilibrium Green method, we try to manipulate the transport properties in molecule consisting of two phenyl-rings via the connected transition metal atoms. The molecule is put between two ZGNR electrodes and the connected transition metal atoms Co, Fe, Mn and Cr are considered. We find that the current across connected transition metal atom Cr system is quite smaller than those across other connected transition metal atoms, and then less attention is paid to the transport properties of Cr connected benzene molecules system. In the parallel and anti-parallel configurations of Co and Fe connected transition metal atom systems, negative differential resistance is found, while in the anti-parallel configuration of Mn connected transition metal atom system, no negative differential resistance is found. At low biases, magnetic resistance happens in Co, Fe and Mn connected atom systems. Spin filtering effects are obtained. Proper analyses are given to explain the above results. In addition, in the above four types of transition metal atom connected systems, the current is too small in Cr connected case, the stability is not good in Fe connected case, and no fine rectification in the anti-parallel configuration. So Co connected case is the best choice.