کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1800143 | 1024508 | 2012 | 5 صفحه PDF | دانلود رایگان |
We theoretically study spin-polarized current through a single electron tunneling transistor (SETT), in which a quantum dot (QD) is coupled to non-magnetic source and drain electrodes via tunnel junctions, and gated by a ferromagnetic (FM) electrode. The I–V characteristics of the device are investigated for both spin and charge currents, based on the non-equilibrium Green's function formalism. The FM electrode generates a magnetic field, which causes a Zeeman spin-splitting of the energy levels in the QD. By tuning the size of the Zeeman splitting and the source–drain bias, a fully spin-polarized current is generated. Additionally, by modulating the electrical gate bias, one can effect a complete switch of the polarization of the tunneling current from spin-up to spin-down current, or vice versa.
► The spin polarized transport through a single electron tunneling transistor is systematically studied.
► The study is based on Keldysh non-equilibrium Green's function and equation of motion method.
► A fully spin polarized current is observed.
► We propose to reverse current polarization by the means of gate voltage modulation.
► This device can be used as a bi-polarization current generator.
Journal: Journal of Magnetism and Magnetic Materials - Volume 324, Issue 15, August 2012, Pages 2392–2396