Optimized magnetoelectric response of doped BFO in hexagonal phase for data transfer

초록

Bismuth ferrite (BiFeO3) is a promising candidate for magnetoelectric spin-orbit (MESO) devices due to its intriguing magnetoelectric properties. This study employs spin-polarized DFT + U calculations to enhance the magnetoelectric response of co-doped BiFeO3 (Bi1-alpha La alpha Fe1-beta X beta O3, where X = Co, Ni, Mn, or Ti) in the hexagonal phase for spintronic random-access memory (RAM) applications. The results indicate that all co-doped systems exhibit 100% spin polarization, identifying them as excellent candidates for data transfer. Among the investigated dopants, LaTi co-doping yielded the lowest magnetization (0.93 MA/m) and a reduced magnetoelectric coupling coefficient (alpha = 1.95 x 10-9 s/m), corresponding to a lower magnetoelectric force of 0.195 mT. In contrast, LaMn co-doping demonstrated the highest structural stability, with a Gibbs free energy of -1.78 x 105 eV and a total magnetic moment of 9.71 mu B${\mu }_B$. This system also exhibited a magnetization of 2.40 MA/m and a significantly enhanced magnetoelectric effect, with a coupling coefficient of alpha = 5.03 x 10-9 s/m and a higher magnetoelectric force of 0.503 mT, making it particularly suitable for data transfer in spintronic RAM.

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