With the full potential linearized augmented plane method, we theoretically investigated the carrier-induced magnetization reversal in digital (Ga,Mn)As heterostructures with varying distance between the two Mn layers along with the distribution and concentration of external carriers. The presence of external holes induces switching from the antiferromagnetic to ferromagnetic state when $d_{\mathrm{Mn}-\mathrm{Mn}}=16.96\AA$, whereas the addition of electrons produces no significant effect. We demonstrate a possibility to separately control $T_c$ and magnetic reversal in digital (Ga,MN)As alloys.

• Received 11 May 2004

DOI:https://doi.org/10.1103/PhysRevLett.94.137206