Spin-dependent transport in molecular tunnel junctions.

We present measurements of magnetic tunnel junctions made using a self-assembled-monolayer molecular barrier. Ni-octanethiol-Ni samples were fabricated in a nanopore geometry. The devices exhibit significant changes in resistance as the angle between the magnetic moments in the two electrodes is varied, demonstrating that low-energy electrons can traverse the molecular barrier while remaining spin polarized. An analysis of the voltage and temperature dependence of the data suggests that the spin-polarized transport signals can be degraded by localized states in the molecular barriers.