Spin accumulation in the parallel-coupled double quantum dots with Rashba spin-orbit interaction connected with ferromagnetic and superconducting electrodes

Abstract

Using the standard nonequilibrium Green’s function techniques, we investigate the effect of Rashba spin-orbit interaction (RSOI) and ferromagnetic electrode on the spin accumulation in the parallel-coupled double quantum dots coupled with a ferromagnetic and a superconducting electrode. It is demonstrated that FM electrode cannot induce the spin polarization of Andreev reflection (AR) current, but can induce the spin accumulation in the QDs. However, RSOI can lead to the spin polarization of AR current as well as the spin accumulation in the QDs. In the existence of RSOI, complete spin-polarized QD can be achieved with negative bias voltage [Formula: see text], which is the most significant advantage of our device. When energy levels [Formula: see text] and the interdot coupling strength [Formula: see text], the maximum value of spin accumulation in this paper is obtained as 0.7. The results may be useful on the design of spintronic devices.