TY - JOUR
T1 - Evidence for Unconventional Strong-Coupling Superconductivity in [Formula presented]
T2 - An Sb Nuclear Quadrupole Resonance Study
AU - Kotegawa, H.
AU - Yogi, M.
AU - Imamura, Y.
AU - Kawasaki, Y.
AU - Zheng, G. q.
AU - Kitaoka, Y.
AU - Ohsaki, S.
AU - Sugawara, H.
AU - Aoki, Y.
AU - Sato, H.
PY - 2003
Y1 - 2003
N2 - We report Sb-NQR results which evidence a heavy-fermion (HF) behavior and an unconventional superconducting (SC) property in [Formula presented] with [Formula presented]. The temperature ([Formula presented]) dependence of nuclear-spin-lattice-relaxation rate, [Formula presented], and NQR frequency unravel a low-lying crystal-electric-field splitting below [Formula presented], associated with [Formula presented]-derived ground state. In the SC state, [Formula presented] shows neither a coherence peak just below [Formula presented] nor a [Formula presented]-like power-law behavior observed for anisotropic HF superconductors with the line-node gap. The isotropic energy gap with its size [Formula presented] seems to open up across [Formula presented] below [Formula presented]. It is surprising that [Formula presented] looks like an isotropic HF superconductor—it may indeed argue for Cooper pairing via quadrupolar fluctuations.
AB - We report Sb-NQR results which evidence a heavy-fermion (HF) behavior and an unconventional superconducting (SC) property in [Formula presented] with [Formula presented]. The temperature ([Formula presented]) dependence of nuclear-spin-lattice-relaxation rate, [Formula presented], and NQR frequency unravel a low-lying crystal-electric-field splitting below [Formula presented], associated with [Formula presented]-derived ground state. In the SC state, [Formula presented] shows neither a coherence peak just below [Formula presented] nor a [Formula presented]-like power-law behavior observed for anisotropic HF superconductors with the line-node gap. The isotropic energy gap with its size [Formula presented] seems to open up across [Formula presented] below [Formula presented]. It is surprising that [Formula presented] looks like an isotropic HF superconductor—it may indeed argue for Cooper pairing via quadrupolar fluctuations.
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U2 - 10.1103/PhysRevLett.90.027001
DO - 10.1103/PhysRevLett.90.027001
M3 - Article
AN - SCOPUS:85038304046
SN - 0031-9007
VL - 90
SP - 4
JO - Physical Review Letters
JF - Physical Review Letters
IS - 2
ER -