MAGNETORESISTANCE AND HOPPING CONDUCTIVITY IN LaMnO3+δ
نویسندگان
چکیده
Resistivity, ρ (T), of LaMnO3+δ displays between δ = 0 − 0.154 an activated behavior both above and below the paramagnetic (PM) to ferromagnetic transition temperature, TC. The relative magnetoresistance at 8 T reaches the values of – 88 % near TC and – 98 % at T ≈ 20 K. In the PM phase ρ (T) satisfies between TC ~130 − 160 K and Tv ∼ 250 − 270 K the Shklovskii – Efros-like variable-range hopping conductivity law, governed by a complex energy dependence of the density of the localized states near the Fermi level.
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