A multi-functional molecular device based on oligo phenylenevinylene and graphene

Using ab initio method, we study the electronic transport for a molecular device consisting of an oligo(p-phenylenevinylene) (OPV) molecule sandwiched between two zigzag-edged graphene nanoribbon (ZGNR) electrodes. Interestingly, a number of electrical functions, including switching, spin-filtering, negative differential resistance and spin-diode, are numerically observed in the device with different OPV conformations respect to ZGNRs and spin configurations in two electrodes. By analyzing the spatial distribution of local density of states, the performance of spin-filtering and -rectifying is explained to the asymmetry distribution of the central molecular orbitals as well as the corresponding coupling to the electrodes.