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

• Substantial tunnel magnetoresistance and perfect spin filtration effects are obtained for SiCNT based MTJ.
• High TMR (∼322%∼322%) suggests its application in spin-valves, MRAMs and other spintronics applications.
• SiCNT is more suitable than CNT for 1D MTJ.
• SiCNT based MTJ shall ensure accurate operation at high temperature and in harsh environmental conditions.

We report first-principles calculations of spin-dependent quantum transport in Fe–SiCNT–Fe magnetic tunnel junction (MTJ). Perfect spin filtration effect and substantial tunnel magnetoresistance are obtained, which suggests SiCNTs as a suitable candidate over CNTs for implementing 1D MTJs. The calculated tunnel magnetoresistance is several hundred percent at zero bias voltage, it reduces to nearly zero after the bias voltage of about 1 V. When the orientation of magnetic configurations of both electrodes is parallel, the zero bias spin injection factor is staggering 99% and remains reasonably high in the range of 60%–75% after the bias voltage of 0.6 V.