TY - JOUR
T1 - Possibility of valence-fluctuatsion-mediated superconductivity in Cd-doped CeIrIn 5 probed by in NQR
AU - Yashima, M.
AU - Tagami, N.
AU - Taniguchi, S.
AU - Unemori, T.
AU - Uematsu, K.
AU - Mukuda, H.
AU - Kitaoka, Y.
AU - Ata, Y.
AU - Honda, F.
AU - Settai, R.
AU - Anuki, Y.
PY - 2012/9/14
Y1 - 2012/9/14
N2 - We report on a pressure-induced evolution of exotic superconductivity and spin correlations in CeIr(In 1-xCd x) 5 by means of in-nuclear-quadrupole-resonance (NQR) studies. Measurements of an NQR spectrum and nuclear-spin-lattice-relaxation rate 1/T 1 have revealed that antiferromagnetism induced by Cd doping emerges locally around Cd dopants, but superconductivity is suddenly induced at T c=0.7 and 0.9 K at 2.34 and 2.75 GPa, respectively. The unique superconducting characteristics with a large fraction of the residual density of state at the Fermi level which increases with T c differ from those for anisotropic superconductivity mediated by antiferromagnetic correlations. By incorporating the pressure dependence of the NQR frequency pointing to the valence change of Ce, we suggest that unconventional superconductivity in the CeIr(In 1-xCd x) 5 system may be mediated by valence fluctuations.
AB - We report on a pressure-induced evolution of exotic superconductivity and spin correlations in CeIr(In 1-xCd x) 5 by means of in-nuclear-quadrupole-resonance (NQR) studies. Measurements of an NQR spectrum and nuclear-spin-lattice-relaxation rate 1/T 1 have revealed that antiferromagnetism induced by Cd doping emerges locally around Cd dopants, but superconductivity is suddenly induced at T c=0.7 and 0.9 K at 2.34 and 2.75 GPa, respectively. The unique superconducting characteristics with a large fraction of the residual density of state at the Fermi level which increases with T c differ from those for anisotropic superconductivity mediated by antiferromagnetic correlations. By incorporating the pressure dependence of the NQR frequency pointing to the valence change of Ce, we suggest that unconventional superconductivity in the CeIr(In 1-xCd x) 5 system may be mediated by valence fluctuations.
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U2 - 10.1103/PhysRevLett.109.117001
DO - 10.1103/PhysRevLett.109.117001
M3 - Article
AN - SCOPUS:84866369870
SN - 0031-9007
VL - 109
JO - Physical Review Letters
JF - Physical Review Letters
IS - 11
M1 - 117001
ER -