A First Principle Study of the Massive TMR in Magnetic Tunnel Junction Using Fe3Al Heusler Alloy Electrodes and MgO Barrier

Abstract

The massive tunnel magnetoresistane (TMR) is expected when Fe3Al Heusler alloy are used for magnetic electrodes in magnetic tunnel junction (MTJ). We demonstrate the Fe3Al/MgO/Fe3Al MTJ, which have good lattice matching interfaces. The electronic and transport properties of these system are systematically investigated by first principle calculation. The electronic band structure of Fe3Al Heusler alloy and MgO are represented for discussion spin filtering effect. Besides, the transmission conductance is calculated to study the spin tunneling effect. We found that the massive TMR is clearly achieved at zero-bias condition, and the TMR is decreased when the finite bias are applied. Thus, among ferromagnetic materials, the Fe3Al Heusler alloy will be good alternative to bcc-Fe based electrodes with MgO barrier for the MTJs beyond.