Characteristics of electronic and spin-independent linear conductance in conjugated aromatic polymer based molecular device

Abstract

Using the non-equilibrium Green's function formalism combined with density-functional theory, we performed a theoretical research to study the electronic and spin-dependent electron transport of a molecular device constructed from a 2-TBQP, 1D-conjugated aromatic polymer(CAP) and 1D-CAP with dihedral angle being 180° sandwiched between two semiinfinite zigzag-edged graphene nanoribbon (zGNR) electrodes. Results show that the proposed 1D-CAP model exhibits an interesting linear conductive behavior, which is much larger than other two models. The intriguing linear current-voltage characteristic can be explained by the well delocalized spatial distribution of frontier orbitals and the separation of electron transmission pathways. Moreover, it's also shown that the spin-charge transport can be modulated by performing the magnetic configuration in zGNR electrodes. The proposed models show many spin related behaviors, such as single spin conductance, dual spin filter and spin-independent linear conductance. The corresponding mechanisms of the above mentioned spin-resolved results can be analyzed and discussed in terms of the spin transmission spectra and the separation of isosurfaces of spin density of these systems.