ﻻ يوجد ملخص باللغة العربية
The self-interaction corrected local spin density (SIC-LSD) formalism and the standard GGA treatment of the exchange-correlation energy have been applied to study the collapse of the magnetic moment of Fe impurities in MgO. The system Mg_{1-x}Fe_xO is believed to be the second most abundant mineral in the Earths lower mantle. We confirm the experimentally found increase of the critical pressure upon iron concentration. Our calculations using standard GGA for a fixed Fe concentration show that different arrangements of Fe atoms can remarkably shift the transition pressure of the high spin (HS) to low spin (LS) transition. This could explain the experimentally found broad transition regions. Our results indicate that the HS-LS transition in Mg$_{1-x}Fe_xO is first order. We find that SIC-LSD fails to predict the divalent Fe configuration as the lowest energy configuration and discuss possible reasons for it.
A characteristic dependence of voltage control of perpendicular magnetic anisotropy (VCMA) on oxygen migration at Fe/MgO interfaces was revealed by performing systematic {it ab initio} study of the energetics of the oxygen path around the interface.
We report on the local electronic structure of Fe impurities in MgO thin films. Using soft x-ray absorption spectroscopy (XAS) we verified that the Fe impurities are all in the 2+ valence state. The fine details in the line shape of the Fe $L_{2,3}$
The self-interaction-corrected local-spin-density approximation is used to describe the electronic structure of dioxides, REO$_2$, and sesquioxides, RE$_2$O$_3$, for the rare earths, RE=Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy and Ho. The valencies of the
Using first-principles calculations, we elucidate microscopic mechanisms of perpendicular magnetic anisotropy (PMA)in Fe/MgO magnetic tunnel junctions through evaluation of orbital and layer resolved contributions into the total anisotropy value. It
A recent experiment reported that robust superconductivity appears in NbTi alloys under ultrahigh pressures with an almost constant superconducting $T_c$ of ~19 K from 120 to 261.7 GPa [J. Guo et al., Adv. Mater. 31, 1807240 (2019)], which is very ra