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تسجيل مستخدم جديدA phenomenological model for the pressure sensitivity of the Curie temperature in hole-doped manganites
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We performed high pressure experiments on La(0.8)Ca(0.2-x)Sr(x)MnO(3) (LCSMO) (0<x< 0.2) ceramic samples in order to analyze the validity of the well known relation between the A mean ionic radius (<rA>) and the Curie temperature Tc of hole-doped manganites at a fixed doping level and for doping values below the 0.3 (Mn+4/Mn+3) ratio. By considering our results and collecting others from the literature, we were able to propose a phenomenological law that considers the systematic dependence of Tc with structural and electronic parameters. This law predicts fairly well the pressure sensitivity of Tc, its dependence with the A-cation radius disorder and its evolution in the high pressure range. Considering a Double Exchange model, modified by polaronic effects, the phenomenological law obtained for Tc can be associated with the product of two terms: the polaronic modified bandwidth and an effective hole doping.
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