First-principles study on tunnel magnetoresistance effect with Cr-doped RuO$_{2}$ electrode

We investigate the functionality of the $\mathrm{Cr}$-doped $\mathrm{RuO_{2}}$ as an electrode of the magnetic tunnel junction (MTJ), motivated by the recent experiment showing that $\mathrm{Cr}$-doping into the rutile-type $\mathrm{RuO_{2}}$ will be an effective tool to control its antiferromagnetic order and the resultant magnetotransport phenomena easily. We perform first-principles calculation of the tunnel magnetoresistance (TMR) effect in the MTJ based on the $\mathrm{Cr}$-doped $\mathrm{RuO_{2}}$ electrodes. We find that a finite TMR effect appears in the MTJ originating from the momentum-dependent spin splitting in the electrodes, which suggests that $\mathrm{RuO_{2}}$ with Cr-doping will work as the electrode of the MTJ. We also show that this TMR effect can be qualitatively captured using the local density of states inside the tunnel barrier.
Comment: 7 pages, 4 figures