Electric field control of single spins in oxide ferroelectric hosts*

Despite the successful scaling of CMOS transistor gate lengths below 10 nm, there has been a corresponding increase in losses as we approach the Boltzmann limit of current control. This problem is a fundamental attribute of devices operating with charge control, but exploiting materials which facilitate the control of single spins opens an avenue to avoid parasitic losses with diminishing feature sizes. We investigate the voltage control of individual spins in magnetically-doped complex oxides as a possible candidate for a CMOS replacement. We show, using first-principles calculations, that electric-field controlled polarization in ferroelectric oxides couples to dopant spins through spin-orbit coupling resulting in an observable magnetization response. Using an in house codebase, we compute the magnetocrystalline anisotropy energy (MCAE) surface and extract the anisotropy constants in Fe and Mn-doped PbTiO₃ and Bi₂WO₆. We predict the spin moment’s dependence on electric-field and present ferroelectric switching pathways that can be used for manipulation. We compare our results with electron paramagnetic resonance measurements of single-spin MCAEs and find they compare favorably with our predictions.