Effect of Interface Morphology on Charge Transport

O.P. Garg¹, Vijay Kr Lamba^2, and D.K. Kaushik³

¹RKSD College Kaithal

²Global College of Engineering & Technology, Khanpur Khui, Punjab

³Shri Jagdishprasad Jhabarmal Tibrewala University

Cite this paper:
O.P. Garg, Vijay Kr Lamba and D.K. Kaushik. Effect of Interface Morphology on Charge Transport. International Journal of Physics. 2015; 3(4):170-174. doi: 10.12691/ijp-3-4-6

Abstract

Molecular devices are a promising candidate for new technology nowadays. Great effort has been devoted recently to understand the charge transport at the interfaces in nano junctions and the role of bond length on the transport properties of molecular junctions. However, these studies have been largely based on the analysis of the low-bias conductance, which does not allow elucidating the exact influence of the symmetry in both the electronic structure and transport characteristics of the interfaces. In this work we had presented a theoretical study of the charge transport, and how conductance changes with varying the bond length of end group anchor (thiol group) on both sides of anthracene molecule to the extreme limits beyond these either the bond broke or it got overlapped with another consecutive bond. Further we rotated (along Z axis) the molecule under observation (anthracene di-thiol) and measured the effect of the rotation on the current and conductance. We have performed first principles calculations of the transport properties of these molecules using a combination of density functional theory and non-equilibrium Green's function techniques.

Keywords:
molecular junction NEGF anchoring molecule DFT green’s function bond length

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