Electrical Curie temperature modulation in (Ga,Mn)As field-effect transistors with Mn composition from 0.027 to 0.200

The authors have fabricated field-effect transistor structures with a ferromagnetic Ga1-xMnxAs channel having Mn composition of x=0.027-0.200. The samples with larger x have higher Curie temperature T-C and hole concentration p, while the controllable range of T-C by applying external electric field does not increase with x. x dependence of effective Mn composition is also described. (c) 2008 American Institute of Physics.