论文标题
界面巨型隧道磁力磁力和散装诱导的大型垂直磁各向异性（111）与FCC铁磁合金的面向（111）的连接：第一原理研究
Interfacial giant tunnel magnetoresistance and bulk-induced large perpendicular magnetic anisotropy in (111)-oriented junctions with fcc ferromagnetic alloys: A first-principles study
论文作者
论文摘要
我们在一系列磁性隧道连接（MTJ）中研究了沿[111]方向的一系列磁性隧道连接（MTJ）中的隧道磁场效应（TMR）效应和磁晶型各向异性。考虑到具有不同$ L1_1 $合金的（111）为导向的MTJ，我们根据第一原则计算计算其TMR比和磁晶型各向异性。分析表明，具有CO基合金（CONI，COPT和COPD）的MTJ具有高于2000美元$ \％$的TMR比率很高。这些MTJ在co $ d $和o $ p $状态之间的界面抗dentbonds在费米级别附近形成。我们发现，抗反键状态的谐振隧道（称为界面谐振隧穿）是获得的高TMR比的起源。我们对磁晶各向异性的计算表明，许多$ L1_1 $合金具有较大的垂直磁各向异性（PMA）。特别是，Copt具有各向异性能量的最大值$ k _ {\ rm u} \左右10 \，{\ rm mj/m^3} $。我们进一步对PMA相对于自旋轨道相互作用进行了扰动分析，并揭示了COPT和CONI中的较大PMA主要来自费米水平附近的自旋控制扰动过程。
We study the tunnel magnetoresistance (TMR) effect and magnetocrystalline anisotropy in a series of magnetic tunnel junctions (MTJs) with $L1_1$-ordered fcc ferromagnetic alloys and MgO barrier along the [111] direction. Considering the (111)-oriented MTJs with different $L1_1$ alloys, we calculate their TMR ratios and magnetocrystalline anisotropies on the basis of the first-principles calculations. The analysis shows that the MTJs with Co-based alloys (CoNi, CoPt, and CoPd) have high TMR ratios over 2000$\%$. These MTJs have energetically favored Co-O interfaces where interfacial antibonding between Co $d$ and O $p$ states is formed around the Fermi level. We find that the resonant tunneling of the antibonding states, called the interface resonant tunneling, is the origin of the obtained high TMR ratios. Our calculation of the magnetocrystalline anisotropy shows that many $L1_1$ alloys have large perpendicular magnetic anisotropy (PMA). In particular, CoPt has the largest value of anisotropy energy $K_{\rm u} \approx 10\,{\rm MJ/m^3}$. We further conduct a perturbation analysis of the PMA with respect to the spin-orbit interaction and reveal that the large PMA in CoPt and CoNi mainly originates from spin-conserving perturbation processes around the Fermi level.
