Quenched disorder suppression of the first-order magnetic phase transition in manganites
نویسندگان
چکیده
The role of quenched disorder on the magnetic phase transition of ferromagnetic manganites is investigated through the field and pressure dependence of magnetization around TC. Our results demonstrate that moderatesmall chemical disorder promotes second-order behavior. This can be rationalized on the basis of a simple thermodynamic model in which the magnetic order parameter is coupled to the lattice, this coupling being sensitive to chemical disorder. A plausible microscopic scenario is also discussed.
منابع مشابه
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