Spin Transport Of The 2DEG Through A Magnetic Barrier With Spin-orbit Interactions

Spintronics is a multidisciplinary field whose central theme is the active manipulation of the spin degree of charge carries for information storage and transmission.The operation of spintronic devices require an efficient spin-injection into conventional semiconductors.Of special interest is to produce an uneven spin population out of an unpolarized source by means of various spin-related transport phenomena(relativistic spin-orbit interaction).In this paper we study the properties of spin transport through a semiconductor 2DEG system subjected to the modulation of both a ferromagnetic metal(FM) stripe on top and the Rashba and Dresselhaus spin-orbit interactions(SOIs).The FM stripe has a magnetization along the transporting direction and generates an inhomogeneous magnetic field in the 2DEG plane which is taken as a double-δshape.Jiang and Jialil have calculater the spin dependent transport properties of the system in the presence of the Rashba effect.And they predict to show magnetoconductance behaviour upon switching the magnetization of the FM.And a large spin polarization up to 90%is obtained.We have shown that there is no spin polarization when the system is modulated only by the magnetic field.A finite spin polarization can be produced when considering the spin-orbit interaction.In low energy region both the magnitude and the orientation of the spin polarization can be tuned by the Rashba strength,the Dresselhaus strength,and the magnetic field strength.It is found that the spin polarization of this system generated from a spin-unpolarized injection can be remarkable only within a low Fermi energy region and is no more than 30%for the parameters available in current experiments.The magnetization reversal of the FM stripe can not result in a change of the conductance.We found that the incident electrons are in a pure spin state rather than a mixted state in their research.