Giant tunnel magnetoresistance with a single magnetic phase-transition electrode
arXiv:1709.00687 · doi:10.1103/PhysRevApplied.9.044034
Abstract
Magnetic phase transition tunnel magnetoresistance (MPT-TMR) effect with a single magnetic electrode has been investigated by first-principles calculations. The calculations show that the MPT-TMR of FeRh/MgO/Cu tunnel junction can be as high as hundreds of percent when the magnetic structure of FeRh changes from G-type antiferromagnetic (GAFM) to ferromagnetic order. This new type of MPT-TMR may be superior to the tunnel anisotropic magnetoresistance because of its huge magneto-resistance effect and similar structural simplicity. The main mechanism for the giant MPT-TMR can be attributed to the formation of interface resonant states at GAFM-FeRh/MgO interface. A direct FeRh/MgO interface is found to be necessary for achieving high MPT-TMR experimentally. Moreover, we find the FeRh/MgO interface with FeRh in ferromagnetic phase has nearly full spin-polarization due to the negligible majority transmission and significantly different Fermi surface of two spin channels. Thus, it may act as a highly efficient and tunable spin-injector. In addition, electric field driven MPT of FeRh-based hetero-magnetic nanostructures can be utilized to design various energy efficient tunnel junction structures and the corresponding lower power consumption devices. Our results will stimulate further experimental investigations of MPT-TMR and other fascinating phenomenon of FeRh-based tunnel junctions that may be promising in antiferromagnetic spintronics.
References in corpus (9)
- Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
- Room-temperature antiferromagnetic memory resistor
- Large magnetoresistance in bcc Co/MgO/Co and FeCo/MgO/FeCo tunneling junctions
- Tunneling anisotropic magnetoresistance and spin-orbit coupling in Fe/GaAs/Au tunnel junctions
- Tunneling anisotropic magnetoresistance driven by resonant surface states: First-principles calculations of Fe(001) surface
- Tunneling anisotropic magnetoresistance in multilayer-(Co/Pt)/AlOx/Pt structures
- Reversal of spin polarization in Fe/GaAs (001) driven by resonant surface states: First-principles calculations
- Tunneling anisotropic magnetoresistance driven by magnetic phase transition
- Tunneling anisotropic magnetoresistance in Fe/GaAs/Au junctions: orbital effects