Electric-field control of ferromagnetism in (Ga,Mn)As

The authors show modulation of Curie temperature T-C and coercivity mu H-0(c) by applying external electric fields E in a ferromagnetic semiconductor (Ga,Mn)As, where a field-effect transistor structure with an Al2O3 gate insulator is utilized. Application of E=+5 (-5) MV/cm decreases (increases) T-C of the channel layer. mu H-0(c) also decreases (increases) with increasing (decreasing) E below T-C. The mechanism of the modulation of mu H-0(c) by E is discussed.