2 research outputs found
Influence of spin waves on transport through a quantum-dot spin valve
We study the influence of spin waves on transport through a single-level
quantum dot weakly coupled to ferromagnetic electrodes with noncollinear
magnetizations. Side peaks appear in the differential conductance due to
emission and absorption of spin waves. We, furthermore, investigate the
nonequilibrium magnon distributions generated in the source and drain lead. In
addition, we show how magnon-assisted tunneling can generate a fullly
spin-polarized current without an applied transport voltage. We discuss the
influence of spin waves on the current noise. Finally, we show how the magnonic
contributions to the exchange field can be detected in the finite-frequency
Fano factor.Comment: published version, 15 pages, 10 figure
Coulomb blockade of spin-dependent shuttling
We show that nanomechanical shuttling of single electrons may enable qualitatively new functionality if spin-polarized electrons are injected into a nanoelectromechanical single-electron tunneling (NEM-SET) device. This is due to the combined effects of spin-dependent electron tunneling and Coulomb blockade of tunneling, which are phenomena that occur in certain magnetic NEM-SET devices. Two effects are predicted to occur in such structures. The first is a reentrant shuttle instability, by which we mean the sequential appearance, disappearance and again the appearance of a shuttle instability as the driving voltage is increased (or the mechanical dissipation is diminished). The second effect is an enhanced spin polarization of the nanomechanically assisted current flow