This study clarified a large dielectric constant of MgO tunnel barriers in epitaxial magnetic tunnel junction (MTJ). The MgO tunnel barrier is subjected to compressive strain because of restraint from the underlying layers. We demonstrated that the dielectric constant of the MgO tunnel barrier and voltage controlled magnetic anisotropy (VCMA) coefficient of the epitaxial MTJ enhanced with increasing the compressive strain. Such strain engineering in epitaxial stacks makes simple rocksalt tunnel barriers more attractive for spintronics applications.
- Tomohiro Nozaki
- Hiroshige Onoda
- Shinji Yuasa
