The effects of arsenic doping on the magnetic properties of CuCr/sub 2/Se/sub 4/

Abstract

In order to further our understanding of a new class of magneto-optical materials, the effects of arsenic doping on the magnetic properties of CuCr/sub 2/Se/sub 4/ have been investigated. Polycrystalline samples were prepared by solid state reaction of fine powders of the involved elements. The solubility of arsenic in CuCr/sub 2/Se/sub 4-x/As/sub x/ is found to be less than 5% (x=0.2). X-ray diffraction data indicates the corresponding increase in the lattice constant a as a result of arsenic doping. The Curie temperature is found to decrease from T/sub c/=330 K to 388 K as doping level is increased from x=0 to 0.1. The saturation moment (measured at 4.5 K and up to 2 T) of the doped sample (x=0.1) is reduced to 4.25 /spl mu//sub /spl beta///formula unit from 4.88 /spl mu//sub B//formula unit, which corresponds to the value for an undoped sample (x=0). A reduction in coercivity is also observed as a result of the doping. These effects are attributed to the increased number of holes in the anion valence band as a result of the arsenic doping. >