Superconductivity above 50 K in Tb(1-x)Th(x)FeAsO

作者：Li Lin Jun^*; Li Yu Ke; Ren Zhi; Luo Yong Kang; Lin Xiao; He Mi; Tao Qian; Zhu Zeng Wei; Cao Guang Han; Xu Zhu An

来源：Physical Review B, 2008, 78(13): 132506.

DOI：10.1103/PhysRevB.78.132506

We have successfully synthesized one member of LnFeAsO (Ln stands for lanthanides) with Ln=Tb. By partial substitution of Tb(3+) by Th(4+), superconductivity with onset T(c) up to 52 K was observed. In the undoped parent compound, the magnetic moments of Tb(3+) ions order antiferromagnetically (AFM) at T(N) of 2.5 K, and there exists an anomaly in the resistivity at T(*) of about 124 K which corresponds to the structural phase transition and/or AFM ordering of magnetic moments of Fe(2+) ions. This anomaly is severely suppressed by Th doping, similar to the cases of F doped LnFeAsO series. Thermopower measurements show that the charge carrier is electronlike for both undoped and Th-doped compounds, and enhanced thermopower in Th-doped samples was observed.

• 出版日期2008-10
• 单位浙江大学