Research Paper: How Alligator-Clip Compounds Affect The I-V Characteristic of Molecular Devices, A DFT Approach

Abstract

In this paper, using density functional theory combined with non-equilibrium Green's function, the effects of alligator-clip compounds on the electronic transport properties of benzene-based molecular devices are investigated. For this purpose, once a single Benzene molecule and once again two Benzene molecules with an acetylene spacer in between are considered as the central element of the molecular device between two gold electrodes. The spin polarization effects in the presence of Nickel and Iron anchors are studied. In the previous studies, other alligator-clip compounds such as Sulfur and organic molecular ones have been utilized. It is important to study the properties and behavior of different elements for the realization of high-performance molecular devices in the future. By utilizing Siesta and Transiesta codes, when excluding spin polarization effects, in all of the structures (except Nickel-Benzene), negative differential resistance is observed. It is an essential property that allows fast switching in certain types of electronic devices. However, when the spin polarization is considered, none of the combinations show the negative differential resistance feature. The I-V characteristics show that all of the combinations have linear behavior in low voltages no matter whether the spin polarization is considered or not. The voltage ranges from -2V to +2V are taken into account in order to investigate the probability of rectification.

Keywords

• molecular electronics
• electronic transport
• benzene-based molecular devices
• alligator-clip
• i-v characteristic