Spin polarization rate calculation for T-shaped double quantum dots coupled to (C- terminated ScC(1 1 1) surface) leads

Abstract

The device considered in our study is the T-shaped double quantum dots system embedded between two ferromagnetic (C-terminated ScC (111) surface) leads. The theoretical treatment is achieved using the time-evolution operator approach. The role of the time-dependent external field, spin-dependent coupling interaction and energy spacing on the dots in spin transport through the device considered in our study has studied. The spin accumulation on the quantum dots, the spin and total currents and the spin polarization rate of the device have calculated. The imprint of the leads density of states is very obvious in the time window calculation which increases with the energy spacing and the frequency of the time-dependent external field. Our results indicate that time-dependent external field and spin-dependent coupling interaction play important role in manufacturing full spin polarization and controlling the spin polarization rate in the device. Controlling the spin transport features have many potential applications in spin-based quantum devices such as quantum computing and spin filter devices.