Conductivity of La 0.75Sr0.25BO3 perovskite-type oxides*

We perform a joint experimental and theoretical study of the conductivity and electronic structures in La$_{0.75}$Sr$_{0.25}A$O$_{3}(A $= Cr, Mn, Fe and Co) with perovskite structure. The samples with pure phase are prepared by the solid reaction. The electrical conductivity measurements indicate that in La$_{0.75}$Sr$_{0.25}A$O$_{3}$ the conductivity orderly increases for Cr, Mn, Fe and Co. The first-principles simulations show that conductivity depends on electronic structure. The d electron increasing in transition metal atoms results in carrier concentration increasing.