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$^{23}$Na NMR Study of Layered Superconductor $Na_xCoO_2- yH_2O$

H. Ohta·C. Michioka·Y. Itoh·K. Yoshimura·H. Sakurai·E. Takayama-Muromachi·K. Takada·T. Sasaki
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Abstract

We measured $^{23}$Na-NMR spectra and nuclear spin-lattice relaxation rates $^{23}(1/T_1)$ of superconducting and non-superconducting bilayer hydrate $Na_xCoO_2-yH_2O$ (x ~ 0.3, y ~ 1.3). The central resonance frequency shows a small but various shift due to the difference in the shielding effect by intercalated $H_2O$ molecules. The different shielding effect also gives a large difference in the magnitude of $^{23}(1/T_1)$.

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H. Ohta, C. Michioka, Y. Itoh, K. Yoshimura, H. Sakurai, E. Takayama-Muromachi, K. Takada, T. Sasaki. 2005-07-05. $^{23}$Na NMR Study of Layered Superconductor $Na_xCoO_2- yH_2O$. https://doi.org/10.1016/j.physb.2006.01.317

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