Giant modulation of magnetism in (Ga,Mn) As ultrathin films via electric field

Taking the advantages of semiconducting properties and carrier-mediated ferromagnetism in (Ga,Mn)As, a giant modulation of magnetism via electric field in (Ga,Mn)As ultrathin film has been demonstrated. Specifically, huge interfacial electric field is obtained by using ionic liquid as the gate dielectric. Both magnetization and transport measurements are employed to characterize the samples, while the transport data are used to analyze the electric filed effect on magnetism. Complete demagnetization of (Ga,Mn)As film is then realized by thinning its thickness down to similar to 2 nm, during which the degradation of ferromagnetism of (Ga,Mn)As ultrathin film induced by quantum confinement effect is suppressed by inserting a heavily-doped p-type GaAs buffer layer. The variation of the Curie temperature is more than 100 K, which is nearly 5-times larger than previous results. Our results provide a new pathway on the efficient electrical control of magnetism.