The synthesis and characterization of 1111-type diluted magnetic semiconductors (La sub( 1-x)Sr sub( x))(Zn sub( 1-x)TM sub( x))AsO (TM = Mn, Fe, Co)

The doping effect of Sr and transition metals Mn, Fe, Co into the direct-gap semiconductor LaZnAsO has been investigated. The results of this study indicate that, the single phase ZrCuSiAs-type tetragonal crystal structure is preserved in (...)(...)AsO (TM = Mn, Fe, Co) with the doping level up to x = 0.1. While the system remains semiconducting, doping with Sr and Mn results in ferromagnetic order with TC similar to 30 K, and doping with Sr and Fe results in a spin-glass-like state below similar to 6K with a saturation moment of similar to 0.02 mu B/Fe, an order of magnitude smaller than the similar to 0.4 mu B/Mn of Sr- and Mn-doped samples. The same type of magnetic state is observed neither for (Zn,Fe) substitution without carrier doping, nor for Sr- and Co-doped specimens. (ProQuest: ... denotes formulae/symbols omitted.)