Magnetic Switching of a Single Molecular Magnet due to Spin-Polarized Current

Magnetic switching of a single molecular magnet (SMM) due to spin-polarized current flowing between ferromagnetic metallic electrodes is investigated theoretically. Magnetic moments of the electrodes are assumed to be collinear and parallel to the magnetic easy axis of the molecule. Electrons tunneling through a barrier between magnetic leads are coupled to the SMM via exchange interaction. The current flowing through the system as well as the spin relaxation times of the SMM are calculated from the Fermi golden rule. It is shown that spin of the SMM can be reversed by applying a voltage between the two magnetic electrodes. Moreover, the switching is reflected in the corresponding current-voltage characteristics.Comment: 5 pages, 4 figures, final version as publishe

Correlation of the angular dependence of spin-transfer torque and giant magnetoresistance in the limit of diffusive transport in spin valves

Angular variation of giant magnetoresistance and spin-transfer torque in metallic spin-valve heterostructures is analyzed theoretically in the limit of diffusive transport. It is shown that the spin-transfer torque in asymmetric spin valves can vanish in non-collinear magnetic configurations, and such a non-standard behavior of the torque is generally associated with a non-monotonic angular dependence of the giant magnetoresistance, with a global minimum at a non-collinear magnetic configuration.Comment: 4 pages, 3 figures, BRIEF REPORT

Spin Diode Behavior in Transport Through Single-Molecule Magnets

We study transport properties of a single-molecule magnet (SMM) weakly coupled to one nonmagnetic and one ferromagnetic lead. Using the diagrammatic technique in real time, we calculate transport in the sequential and cotunneling regimes for both ferromagnetic and antiferromagnetic exchange coupling between the molecule's LUMO level and the core spin. We show that the current flowing through the system is asymmetric with respect to the bias reversal, being strongly suppressed for particular bias polarizations. Thus, the considered system presents a prototype of a SMM spin diode. In addition, we also show that the functionality of such a device can be tuned by changing the position of the molecule's LUMO level and strongly depends on the type of exchange interaction.Comment: 6 pages with 4 EPS figure