Spin Hall effect in doped ferroelectric HfO2

The spin Hall effect (SHE) enables charge-to-spin conversion by electrical means and is promising for spintronic applications. Here, we report on the intrinsic spin Hall effect in the prototypical ferroelectric material HfO2 with charge doping using density functional theory calculations and theoretical analysis. We show that ferroelectric displacements are insensitive to charge doping and are sustained up to a large doping concentration of 0.4 electrons or holes per unit cell volume. In addition, the large spin Hall conductivity in the vicinity of the band edges is well preserved. Intriguingly, we demonstrate the giant spin Hall efficiency characterized by the sizable spin Hall angle of ∼0.1 in doped HfO2. These results add unexplored functionality to ferroelectric HfO2 and open opportunities for potential device applications.