Special magnetic phenomena in heavily doped La0.7-xDyxSr0.3MnO3 system

• 来源期刊: 中国科学G辑（英文版）
• 年，卷（期）: 2008,（1）
• 页码范围: 90-97
• 页数: 8页
• 语种: 英文

摘要

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3 (0.40≤x≤0.70) system is studied in this paper. The M-T relation seems to be complicated with the increase of x. For sample with x = 0.40, AFM behavior exists at T≤TN and M-T curves under zero field cooling (ZFC) and field cooling (FC) exhibit typical behavior of spin- cluster glass state above TN. For the sample with x = 0.50, the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below TN. For samples with x = 0.60, 0.70, their ZFC M-T curves are similar to that of x = 0.50, but the FC M-T curves do not exhibit negative values any more. All the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical temperatures. The molecular field theory fits well the negative magnetization for x = 0.50.