First-principles study of spin transport in CrO2-SiCNT-CrO2 magnetic tunnel junction

摘要

We report the spin transport in silicon carbide nanotube based magnetic tunnel junction with half-metallic-ferromagnet CrO2 as electrodes. The simulations based on first principles suggest high tunnel magnetoresistance similar to 100 % at zero bias, TMR remains high at higher bias voltages. I-V characteristics show that spin current in parallel magnetic configuration is much higher than the spin current in anti-parallel configuration. Perfect spin-filtration effect is obtained for this structure. Transmission coefficients are also calculated to understand the spin and bias dependent non-equilibrium transport properties.