(New diluted ferromagnetic semiconductor with Curie temperature up to 180 K and isostructural to the ‘122’ iron-based superconductors）
K. Zhao, Z. Deng, X.C. Wang, W. Han, J.L. Zhu, X. Li, Q.Q. Liu, R.C. Yu, T. Goko, B. Frandsen, L. Liu, F.L. Ning, Y.J. Uemura, H. Dabkowska, G.M. Luke, H. Luetkens, E. Morenzoni, S.R. Dunsiger, A. Senyshyn, P. Boni, C.Q. Jin
Diluted magnetic semiconductors have received much attention due to their potential applications for spintronics devices. A prototypical system (Ga,Mn)As has been widely studied since the 1990s. The simultaneous spin and charge doping via hetero-valent (Ga3+,Mn2+) substitution, however, resulted in severely limited solubility without availability of bulk specimens. Here we report the synthesis of a new diluted magnetic semiconductor (Ba1-xKx)(Zn1-yMny)2As2, which is isostructural to the 122 iron-based superconductors with the tetragonal ThCr2Si2 (122) structure. Holes are doped via (Ba2+, K1+) replacements, while spins via isovalent (Zn2+,Mn2+) substitutions. Bulk samples with x=0.1~0.3 and y=0.05~0.15 exhibit ferromagnetic order with Tc up to 180 K, which is comparable to the highest Tc for (Ga,Mn)As and significantly enhanced from Tc up to 50 K of the ‘111’-based Li(Zn,Mn)As. Moreover, ferromagnetic (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 for the development of multilayer functional devices.