TY - JOUR
T1 - Evidence for d-wave pairing in the cobalt oxide superconductor Nax CoO2 · 1.3 H2 O
AU - Matano, K.
AU - Zheng, Guo Qing
AU - Chen, D. P.
AU - Lin, C. T.
PY - 2008/4/1
Y1 - 2008/4/1
N2 - We report the spin susceptibility in the superconducting state of the cobalt oxide superconductor Nax CoO2 · 1.3 H2 O, via the 59Co Knight shift measurements. Along both a- and c-axis directions, the shift decreases below Tc. At T = 1.7 K, the shift along the a-axis, Ka, increases with increasing the strength of magnetic field (H), following a sqrt(H) variation. Together with the T3 dependence of the spin-lattice relaxation rate, 1 / T1, these results indicate unambiguously that the Cooper pairs are in the spin-singlet form and that there exist nodes in the gap function. The data are most consistent with a d-wave symmetry.
AB - We report the spin susceptibility in the superconducting state of the cobalt oxide superconductor Nax CoO2 · 1.3 H2 O, via the 59Co Knight shift measurements. Along both a- and c-axis directions, the shift decreases below Tc. At T = 1.7 K, the shift along the a-axis, Ka, increases with increasing the strength of magnetic field (H), following a sqrt(H) variation. Together with the T3 dependence of the spin-lattice relaxation rate, 1 / T1, these results indicate unambiguously that the Cooper pairs are in the spin-singlet form and that there exist nodes in the gap function. The data are most consistent with a d-wave symmetry.
KW - NMR
KW - Na CoO · y H O
KW - Superconductivity
KW - d-Wave symmetry
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U2 - 10.1016/j.physb.2007.10.251
DO - 10.1016/j.physb.2007.10.251
M3 - Article
AN - SCOPUS:39749124944
SN - 0921-4526
VL - 403
SP - 1107
EP - 1108
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
IS - 5-9
ER -