Microscopic coexistence of antiferromagnetic order and superconductivity in Ba$_{0.77}$K$_{0.23}$Fe$_{2}$As$_{2}$

Z. Li; R. Zhou; D. L. Sun; J. Yang; C. T. Lin; Guo-qing Zheng

doi:10.1103/PhysRevB.86.180501

paper

Microscopic coexistence of antiferromagnetic order and superconductivity in Ba $_{0.77}$ K $_{0.23}$ Fe $_{2}$ As $_{2}$

arXiv:1204.2434 · doi:10.1103/PhysRevB.86.180501

Abstract

We report ^{75}As nuclear magnetic resonance studies on an underdoped single-crystal Ba0.77K0.23Fe2As2 with Tc = 16.5 K. Below T_N = 46 K, the NMR peaks for H//c split and those for H //a shift to higher frequencies, which indicates that an internal magnetic field along the c axis develops below T_N. The spin-lattice relaxation rate 1/T_1 measured at the shifted peak with H//a, which experiences the internal field, shows a distinct decrease below Tc(Î¼_0H = 12 T) = 16 K, following a T^3 relation at low temperatures. Our results show unambiguously that antiferromagnetic order and superconductivity coexist microscopically. The unusual superconducting state with the coexisting magnetism is highlighted.

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Microscopic coexistence of antiferromagnetic order and superconductivity in Ba0.77​K0.23​Fe2​As2​

Abstract

Microscopic coexistence of antiferromagnetic order and superconductivity in Ba $_{0.77}$ K $_{0.23}$ Fe $_{2}$ As $_{2}$