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arXiv · 0812.3198

Conventional $s$-Wave Superconductivity in Noncentrosymmetric Ir$_2$Ga$_9$: $^{71}$Ga-NQR Evidence

A. Harada·N. Tamura·H. Mukuda·Y. Kitaoka·K. Wakui·S. Akutagawa·J. Akimitsu
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Abstract

We report a $^{71}$Ga nuclear-quadrupole-resonance (NQR) study on the characteristics of superconductivity in noncentrosymmetric Ir$_2$Ga$_9$ at zero field (H=0). The $^{71}$Ga-NQR measurements have revealed that $1/T_1$ has the clear coherence peak just below $T_{\rm c}$, and decreases exponentially upon further cooling in Ir$_2$Ga$_9$. From these results, Ir$_2$Ga$_9$ is concluded to be the conventional s-wave superconductor. Despite the lack of spatial centrosymmetry, there are no evidence for unconventional superconducting state ascribed to ASOC in Ir$_2$Ga$_9$.

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A. Harada, N. Tamura, H. Mukuda, Y. Kitaoka, K. Wakui, S. Akutagawa, J. Akimitsu. 2008-12-19. Conventional $s$-Wave Superconductivity in Noncentrosymmetric Ir$_2$Ga$_9$: $^{71}$Ga-NQR Evidence. https://doi.org/10.1143/jpsj.78.025003

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