  We propose a method to realize diluted magnetic semiconductors (DMS) with p-
and n-type carriers by choosing host semiconductors with a narrow band gap. By
employing a combination of the density function theory and quantum Monte Carlo
simulation, we demonstrate such semiconductors using Mn-doped BaZn2As2, which
has a band gap of 0.2 eV. In addition, we found a new non-toxic DMS Mn-doped
BaZn2Sb2, of which the Curie temperature Tc is predicted to be higher than that
of Mn-doped BaZn2As2, the Tc of which was up to 230 K in the recent experiment.
