  Diluted magnetic semiconductors (DMS) have received much attention due to its
potential applications to spintronics devices. A prototypical system (Ga,Mn)As
has been widely studied since 1990s. The simultaneous spin and charge doping
via hetero-valence (Ga3+,Mn2+) substitution, however, resulted in severely
limited solubility without availability of bulk specimens. Previously we
synthesized a new diluted ferromagnetic semiconductor of bulk Li(Zn,Mn)As with
Tc up to 50K, where isovalent (Zn,Mn) spin doping was separated from charge
control via Li concentrations. Here we report the synthesis of a new diluted
ferromagnetic semiconductor (Ba1-xKx)(Zn1-yMny)2As2, isostructural to iron 122
system, where holes are doped via (Ba2+, K1+), while spins via (Zn2+,Mn2+)
substitutions. Bulk samples with x=0.1-0.3 and y=0.05-0.15 exhibit
ferromagnetic order with TC up to 180K, comparable to that of record high Tc
for Ga(MnAs), significantly enhanced than Li(Zn,Mn)As. Moreover the
(Ba,K)(Zn,Mn)2As2 shares the same 122 crystal structure with semiconducting
BaZn2As2, antiferromagnetic BaMn2As2, and superconducting (Ba,K)Fe2As2, which
makes them promising to the development of multilayer functional devices.
