Giant Magnetic and Optical Anisotropy in Cerium-Substituted M-Type Strontium Hexaferrite Driven by <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mn>4</mml:mn><mml:mi>f</mml:mi></mml:math> Electrons

By performing density-functional calculations, we find a giant magnetocrystalline anisotropy (MCA) constant in abundant element cerium ($\mathrm{Ce}$) substituted M-type hexaferrite, the energetically favorable strontium site, assisted by quantum confined electron transfer from $\mathrm{Ce}$ to specific iron ($2a$) site. Remarkably, calculated electronic structure shows that leads formation of ${\mathrm{Ce}}^{3+}$ and ${\mathrm{Fe}}^{2+}$ at $2a$ site producing an occupied $\mathrm{Ce}$($4{f}^{1}$) state below Fermi level adds significant contribution MCA magnetic moment. A half substitution forms metallic state, while full retains semiconducting hexaferrite (host). In latter, band gap is reduced due charge-transferred states region host. The optical absorption coefficient enhanced between light polarization parallel perpendicular directions. Calculated energies, including analysis probable competing phases, elastic constants confirm both compositions are chemically mechanically stable. With successful synthesis, can be alternative high-performing critical-element-free permanent magnet material adapted for use devices such as automotive traction drive motors.