Perfect spin filtering controlled by an electric field in a bilayer graphene junction: Effect of layer-dependent exchange energy

Jatiyanon Kitakorn¹, Tang I-Ming², Soodchomshom Bumned^{1, †,}

Plot of spin conductance versus electric field-induced gap Δ_E in the case of (a) a P-junction with E = U = 5 meV, (b) an AP-junction with E = U = 5 meV, (c) a P-junction with E = U = 30 meV, and (d) an AP-junction with E = U = 30 meV, respectively. As is seen, the perfect (or complete) spin filter by varying electric field occurs only for the AP configuration.