The structures, magnetism, and electronic transport properties of the semiconducting (La1+xCa1-x)CoRuO6 double perovskites (-0.25<x<0.25) have been investigated. Lattice parameters, antisite disorder, the Neel temperature and resistivities are found to vary in a systematic manner with x. The Co-Ru antisite disorder is minimal at x=0, showing that this disorder is driven by the mixed Co or Ru electronic states at \x\not equal0 rather than by La/Ca cation mixing. Hole doping (x<0) decreases the resistivity by two orders of magnitude without significantly changing the magnetization, whereas electron doping (x>0) enhances the magnetization with little change to the resistivity, perhaps signaling the formation of magnetic clusters. LaCaCoRuO6 orders antiferromagnetically at T-N=96 K, accompanied by a magnetostrictive anomaly. The Co/Ru spin structure, with a magnetic vector k=(1/2,0,1/2), cannot be determined unambiguously from neutron powder diffraction data.
|Number of pages||6|
|Journal||Physical Review B: Condensed Matter and Materials Physics|
|Publication status||Published - 1 Mar 2004|