Metallization and magnetic order in EuB6
نویسندگان
چکیده
We present the results of fieldand temperature-dependent resistivity r and magnetization M measurements which show that colossal magnetoresistance in semimetallic EuB6 is not associated with its bulk Curie temperature TC512.6 K, determined by a scaling analysis of M (H ,T), but with a second phase transition at TM515.5 K. We propose that metallization occurs at TM via the overlap of magnetic polarons. The separation of the charge delocalization and bulk magnetic ordering transitions implies electronic and magnetic phase separation.
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