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Anomalous NMR Magnetic Shifts in CeCoIn_5

N. J. Curro·B. Simovic·P. C. Hammel·P. G. Pagliuso·G. B. Martins·J. L. Sarrao·J. D. Thompson
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Abstract

We report ^{115}In and ^{59}Co Nuclear Magnetic Resonance (NMR) measurements in the heavy fermion superconductor CeCoIn_5 above and below T_c. The hyperfine couplings of the In and Co are anisotropic and exhibit dramatic changes below 50K due to changes in the crystal field level populations of the Ce ions. Below T_c the spin susceptibility is suppressed, indicating singlet pairing.

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N. J. Curro, B. Simovic, P. C. Hammel, P. G. Pagliuso, G. B. Martins, J. L. Sarrao, J. D. Thompson. 2001-05-08. Anomalous NMR Magnetic Shifts in CeCoIn_5. https://doi.org/10.1103/physrevb.64.180514

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