Enhancing the Superconducting Transition Temperature in the Absence of Spin Correlations in Heavy Fermion Compound CeIrIn$_5$

Shinji Kawasaki; Guo-qing Zheng; Hiroki Kan; Yoshio Kitaoka; Hiroaki Shishido; Yoshichika Ōnuki

doi:10.1103/physrevlett.94.037007

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Enhancing the Superconducting Transition Temperature in the Absence of Spin Correlations in Heavy Fermion Compound CeIrIn$_5$

Shinji Kawasaki·Guo-qing Zheng·Hiroki Kan·Yoshio Kitaoka·Hiroaki Shishido·Yoshichika Ōnuki

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Abstract

We report on a pressure($P$)-induced evolution of superconductivity and spin correlations in CeIrIn$_5$ via the $^{115}$In nuclear-spin-lattice-relaxation rate measurements. We find that applying pressure suppresses dramatically the antiferromagnetic fluctuations that are strong at ambient pressure. At $P$ = 2.1 GPa, $T_{\rm c}$ increases to $T_{\rm c}$ = 0.8 K that is twice $T_{\rm c}$($P$ = 0 GPa), in the background of Fermi liquid state. This is in sharp contrast with the previous case in which negative, chemical pressure (replacing Ir with Rh) enhances magnetic interaction and increases $T_{\rm c}$. Our results suggest that multiple mechanisms work to produce superconductivity in the same compound CeIrIn$_5$.

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Shinji Kawasaki, Guo-qing Zheng, Hiroki Kan, Yoshio Kitaoka, Hiroaki Shishido, Yoshichika Ōnuki. 2004-12-22. Enhancing the Superconducting Transition Temperature in the Absence of Spin Correlations in Heavy Fermion Compound CeIrIn$_5$. https://doi.org/10.1103/physrevlett.94.037007

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