Giant tunneling magnetoresistance in FeCrSi/FeTiSi/FeCrSi magnetic tunnel junction
arXiv:2311.01772
Abstract
We propose a theoretical model for an all-Heusler magnetic tunnel junction that uses two Heusler compounds: FeCrSi and FeTiSi, both of which can be experimentally synthesized. FeCrSi is a half-metallic ferromagnet, making it a promising material for efficient spin injection in magnetic random access memories and other spin-dependent devices. While, FeTiSi is a nonmagnetic semiconductor that has the same lattice structure and comparable lattice constant with FeCrSi, as it can be obtained by substituting the -site atoms in FeCrSi. By using FeTiSi as a tunneling barrier sandwiched by two pieces of semi-infinite FeCrSi to construct an all-Heusler magnetic tunnel junction, the interface disorder is naturally reduced. Our calculations demonstrate that this magnetic tunnel junction can exhibit a giant tunneling magnetoresistance of up to 10\% and remains robust under finite bias voltage. These characteristics suggest that FeCrSi/FeTiSi/FeCrSi MTJ will be an ideal candidate for future spintronic applications. More importantly, such a device model can keep such a giant tunneling magnetoresistance at and beyond room temperature due to the high Curie temperature of FeCrSi.
13 pages, 5 figures