Ba(Zn(1−2x)Mn(x)Cu(x))(2)As(2): A Bulk Form Diluted Ferromagnetic Semiconductor with Mn and Cu Codoping at Zn Sites

We report the synthesis and characterization of a bulk form diluted magnetic semiconductor Ba(Zn(1−2x)Mn(x)Cu(x))(2)As(2) [Image: see text] with the crystal structure identical to that of “122” family iron based superconductors and the antiferromagnet BaMn(2)As(2). No ferromagnetic order occurs with (Zn, Mn) or (Zn, Cu) substitution in the parent compound BaZn(2)As(2). Only when Zn is substituted by both Mn and Cu simultaneously, can the system undergo a ferromagnetic transition below T(C) ~ 70 K, followed by a magnetic glassy transition at T(f) ~ 35 K. AC susceptibility measurements for Ba(Zn(0.75)Mn(0.125)Cu(0.125))(2)As(2) reveal that T(f) strongly depends on the applied frequency with [Image: see text] and a DC magnetic field dependence of [Image: see text], demonstrating that a spin glass transition takes place at T(f). As large as −53% negative magnetoresistance has been observed in Ba(Zn(1−2x)Mn(x)Cu(x))(2)As(2), enabling its possible application in memory devices.