Magnetic and Transport Properties of the Kondo Lattice Model with Ferromagnetic Exchange Coupling
نویسنده
چکیده
The Kondo lattice model with Hund’s ferromagnetic spin coupling is investigated as a microscopic model of the perovskite-type 3d manganese oxide R1−xAxMnO3 where R and A are rare earth element and alkaline earth element, respectively. We take the classical spin limit S = ∞ for the simplicity of the calculation, since the quantum exchange process seems to be irrelevant in the high temperature paramagnetic phase. Magnetic and transport properties of the system are calculated. In the hole doped systems, ferromagnetic instabilities are observed as the temperature is lowered. The giant magnetoresistance of this model is in excellent agreement with the experimental data of La1−xSrxMnO3.
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