Magnetic flux assisted spin accumulation in a quantum dot ring with Rashba spin-orbital interaction

The spin accumulation in a single quantum dot (QD) ring is investigated in the presence of both a magnetic flux penetrating though it and the Rashba spin-orbital (RSO) interaction. The RSO interaction, which is assumed to exist only in the QD and other regions are free from it, induces a spin-dependent phase factor (spin precession) in the line-width function and thus making the spin-up and spin-down electrons have different interference effect when they are combined. We show that both the magnitude and the directions of the spin accumulation can be efficiently controlled by the co-action of the RSO effect, the magnetic flux, the bias voltage, etc. Moreover, one can fix the RSO-induced phase factor and switch on or off the spin accumulation in terms of the magnetic flux, which can act as a spin polarization switcher.