Channel thickness dependence of the magnetic properties in (Ga,Mn)As FET structures

We have fabricated a series of field-effect transistor structures with a thin (Ga,Mn)As channel with thickness t of 3.5, 4.0, 4.5, and 5.0 nm, and investigated the effect of electric-field E on their magnetic properties. The Curie temperature T (C) showed a clear dependence on the magnitude of E, and its controllable range became larger with decreasing t and reached 15 K for the device with t=3.5 nm, which corresponded to 32% of T (C) of the layer.