Transport and magnetic properties of La 1-x Ba x CoO 3

摘要: We have systematically investigated transport, magnetic, and structural properties of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ba}}_{x}{\mathrm{CoO}}_{3}$ in the range doping $0lx\ensuremath{\leqslant}0.55$. In this system, metal-insulator transition is observed to be coincident with onset ferromagnetic (FM) ordering at $x=0.20$. Well below Curie temperature ${T}_{C}$, $\ensuremath{\rho}$ exhibits ${T}^{2}$ behavior whereas over a interval just it shows ${T}^{4}$ dependence due scattering charge carriers by magnetic fluctuations. For $xl0.20$, low property dominated spin-glass- or cluster-glasslike phase. The role ionic size mismatch on above mentioned physical has also been partially substituting $\mathrm{La}$ $\mathrm{Nd}$ $\mathrm{Ba}$ $\mathrm{Sr}$ for fixed doping. A phase diagram, temperatures $(x)$, constructed from study.