Department of Physics, Renmin University of China, Beijing 100872, China.
Phys Rev Lett. 2012 Nov 9;109(19):197002. doi: 10.1103/PhysRevLett.109.197002. Epub 2012 Nov 7.
We use (75)As nuclear magnetic resonance to investigate the local electronic properties of Ba(Fe(1-x)Ru(x))(2)As(2) (x = 0.23). We find two phase transitions: to antiferromagnetism at T(N) ≈ 60 K and to superconductivity at T(C) ≈ 15 K. Below T(N), our data show that the system is fully magnetic, with a commensurate antiferromagnetic structure and a moment of 0.4μ(B)/Fe. The spin-lattice relaxation rate 1/(75)T(1) is large in the magnetic state, indicating a high density of itinerant electrons induced by Ru doping. On cooling below T(C), 1/(75)T(1) on the magnetic sites falls sharply, providing unambiguous evidence for the microscopic coexistence of antiferromagnetism and superconductivity.
我们使用（75）核磁共振来研究 Ba(Fe(1-x)Ru(x))(2)As(2)（x = 0.23）的局部电子性质。我们发现了两个相变：在 T(N) ≈ 60 K 处转变为反铁磁性，在 T(C) ≈ 15 K 处转变为超导性。在 T(N)以下，我们的数据表明该系统是完全磁性的，具有准反铁磁结构和 0.4μ(B)/Fe 的磁矩。自旋晶格弛豫率 1/(75)T(1)在磁性状态下很大，表明 Ru 掺杂诱导了高浓度的巡游电子。在冷却到 T(C)以下时，磁性位的 1/(75)T(1)急剧下降，为反铁磁性和超导性的微观共存提供了明确的证据。
