Gate control of spin-layer-locking FETs and application to monolayer LuIO

peer reviewed / A recent 2D spinFET concept proposes to switch electrostatically between two separate sublayers with strong and opposite intrinsic Rashba effects, exploiting the spin-layer locking mechanism in centrosymmetric materials with local dipole fields. Here, we propose a novel monolayer material within this family, lutetium oxide iodide (LuIO). It displays one of the largest Rashba effects among 2D materials (up to $k_R = 0.08 \si{\angstrom}^{-1}$), leading to a $\pi/2$ rotation of the spins over just 1 nm. The monolayer was predicted to be exfoliable from its experimentally-known 3D bulk counterpart, with a binding energy lower than graphene. We characterize and simulate the interplay of the two gate-controlled parameters for such devices: doping and spin channel selection. We show that the ability to split the spin channels in energy diminishes with doping, leading to specific gate-operation guidelines that can apply to all devices based on spin-layer locking.