Spin transport in bimetallocene

Abstract

I present a theoretical study on the spin-transport behavior of bimetallocenes of cobalt or nickel, wherein electronic communication between the two metal centers can be efficiently performed via a fulvalene ligand. The transmission of electrons in the bimetallocene connected to two gold electrodes was calculated using a first-principles density functional method. Spin transport was estimated from the difference between the transmissions of the spin-up and spin-down states. Results revealed that bicobaltocene has a perfect spin-filtering effect because the supply of excess electrons to the electronic state of ferrocene causes a split in the energy levels of the spin-up and spin-down states. As surmised, it was found that spin polarization was caused by strong interactions between the two metal centers via the fulvalene ligand. Furthermore, bicobaltocene exhibited a negative differential resistance at a relatively low bias voltage.