Some Doping Effects on the Semiconducting Properties of Gd_2CuO_4
Some doping effects on the semiconducting properties of the Gd_2CuO_4 compound were investigated. The ZrO_2 or ThO_2 (0.5 mol%) lowered the resistivity of the Gd_2CuO_4 at room temperature by a factor of 10^4. The thermoelectric powers of the same samples were negative. These were explained as being due to the Cu^+ ions formed by the dopants. The CaO dopant lowered the resistivity by a factor of ten and converted the sign of the thermoelectric power from negative to positive. The resistivity of the BaO-doped samples increased with an increase in the dopant concentration up to 0.5 mol% and decreased with an increase in the dopant concentration in the concentration region lower than that. This suggested that the dopant of BaO was less effective on the resistivity-lowering than was the CaO. The samples doped with the ZrO_2 and CaO simultaneously gave a trend similar to those doped with the BaO in the concentration dependence of the resistivity. Silver oxide and indium oxide were also employed as dopants, but no doping effects were observed on either resistivity or the lattice parameters.
- Science reports of the Research Institutes, Tohoku University. Ser. A, Physics, chemistry and metallurgy
Science reports of the Research Institutes, Tohoku University. Ser. A, Physics, chemistry and metallurgy 25 161-161, 1974