Electronic transport in Si and Au monoatomic chains considering strongly correlation effect, a first principle study

Subject Areas : Journal of Physical & Theoretical Chemistry

Mansoureh Pashangpour ¹ , Vahid Ghaffari ²

1 - Department of Physics, Islamshahr Branch, Islamic Azad University, Islamshahr, Iran
2 - Central Tehran Branch, Islamic Azad University, Tehran, Iran

Received: 2016-02-25 Accepted : 2016-04-25 Published : 2016-06-20

Keywords: Density functional theory, Density of state, Quantum transport, Strongly correlated&#x0D, &#x0D, system W,

Abstract :

We have investigated structure and electronic properties of Au and Si liner chains using the firstprinciplesplane wave pseudopotential method. The transport properties and conductance of these twoliner chains are studied using Landauer approaches based on density functional theory (DFT). Weobtain density of states and band gap using Kohn-Sham and Wannier functions as well as quantumconductivity and current for Au and Si liner chains. We study the effect of Hubbard U on quantumconductivity and current for Au liner chain within DFT+U for strongly correlated systems. Wecompare the source of the states around Fermi level of these systems that have important role inconductivity. We present I-V characteristics of the Si and Au liner chain. Results show Ohmicbehavior of current flow in the liner chains in terms of applied bias voltage. We show that Hubbard Ucorrection removes the unphysical contribution of d electrons to the conductance of Au liner chain,resulting in a single transmission channel and a more realistic conductance of 1G0 that is in goodagreement with experimental results. Our calculations reveal that monatomic chains of Si and Au aremetallic therefore they can be used as connectors between nanoelectronic devices.