Designing multi-functional devices based on two benzene rings molecule modulated with Co and N atoms

Abstract

We investigate the electronic transport properties in molecular devices consisting of two phenyl-rings connected by Co and N atoms by using nonequilibrium Green’s function method and density function theory. The molecule is coupled to two zigzag graphene nanoribbon electrodes. It is found that giant magnetoresistance effect exists in both the coplanar and the perpendicular conformations at low biases. And the total current decreases a lot, on order of 100, when the orientation of the phenyl ring changes from coplanar site to perpendicular site. This indicates a molecular switcher via conformational control. What’s more, perfect dual spin-filtering effect and rectifying behavior can be realized by modulating the external magnetic field. So a multi-functional device is achieved in our designed molecular junction. Detailed explanations via transmission spectra, distribution of molecular projected self-consistent Hamiltonian states are given to the above useful phenomenon.