Structure, transport and magnetism of La_0.67Ca_0.33Mn_1−xTa_xO₃

详细信息    查看全文

• 作者：L. Seetha Lakshmi ; K. Dö ; rr ; K. Nenkov ; V. Sridharan ; V. Sankara Sastry ; K.-H. Mü ; ller
• 关键词：Manganites ; Mn site substitution ; Ta ; Transport properties ; Cluster glass
• 刊名：Journal of Magnetism and Magnetic Materials
• 出版年：2005
• 出版时间：April 2005
• 年：2005
• 卷：290-291
• 期：Complete
• 页码：924-927
• 全文大小：139 K

文摘

For the first time, the effect of Ta⁵⁺ substitution at the Mn site of La_0.67Ca_0.33MnO₃ compound is reported. A significant increase in lattice parameters and unit cell expansion indicate larger structural modification upon substitution. The ferromagnetic-metallic ground state is modified to a cluster glass insulator for x>0.03. The observed suppression of the ferromagnetic transition temperature T_c of 39 K/at % might be the highest reported in Mn-site substituted La_0.67Ca_0.33MnO₃. The well-known effects of changed carrier density, larger average ionic radius at Mn site and dilution of Mn sublattice appear insufficient to explain this strong suppression of T_C.