Controllable spin polarization in an organic molecule

The spin transport properties of an organic molecule (1,41,4-2-phenyl-dithiolate) in the presence of the Rashba spin–orbit effect as well as a transverse (in-plane) electric field are calculated. We show that, for an appropriate amount of Rashba spin–orbit coefficient, the spin polarization of the outgoing electrons can be easily controlled by changing the transverse electric field. Also, by changing the transverse electric field periodically, the molecule can work as a “spin clock” which can potentially have a very high switching speed because the capacitance of the molecule is very small. The results can be used for designing molecular spintronic devices.

► Spin-polarized transport through an organic molecule can be fully controlled by Rashba spin–orbit effect and a transverse electric field.
► Correct tuning of the amount of Rashba spin–orbit effect and external electric field are necessary to obtain desired results.
► By changing the electric field periodically, a “spin clock” with high switching speed is obtainable.