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arXiv · 0903.2011

NMR investigation of superconductivity and antiferromagnetism in CaFe$_2$As$_2$ under pressure

S. -H. Baek·H. Lee·S. E. Brown·N. J. Curro·E. D. Bauer·F. Ronning·T. park·J. D. Thompson
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Abstract

We report $^{75}$As NMR measurements in CaFe$_2$As$_2$, made under applied pressures up to 0.83 GPa produced by a standard clamp pressure cell. Our data reveal phase segregation of paramagnetic (PM) and antiferromagnetic (AFM) phases over a range of pressures, with the AFM phase more than 90 % dominant at low temperatures. In situ RF susceptibility measurements indicate the presence of superconductivity. $^{75}$As spin-lattice relaxation experiments indicate that the $^{75}$As nuclei sample the superconductivity while in the magnetically-ordered environment.

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S. -H. Baek, H. Lee, S. E. Brown, N. J. Curro, E. D. Bauer, F. Ronning, T. park, J. D. Thompson. 2009-06-04. NMR investigation of superconductivity and antiferromagnetism in CaFe$_2$As$_2$ under pressure. https://doi.org/10.1103/physrevlett.102.227601

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