Ferromagnetic semiconductor (In,Ga,Mn)As with Curie temperature above 100 K

Abstract

We have grown (InyGa1−y)1−xMnxAs ferromagnetic semiconductor layers with Mn composition of x up to 0.13 on InP substrates by molecular beam epitaxy. Near the lattice-matched composition, i.e., y∼0.53, the Curie temperature increases linearly with the ferromagnetically effective Mn composition xeff, following the empirical equation TC=1300×xeff. We obtained Curie temperatures above 100 K when x is relatively high (x>0.1; xeff⩾0.08) and the hole concentration is of the order of 1019 cm−3.