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arXiv · 1207.0215

Superconductivity in the Ferroquadrupolar State in the Quadrupolar Kondo Lattice PrTi$_2$Al$_{20}$

Akito Sakai·Kentaro Kuga·Satoru Nakatsuji
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Abstract

The cubic compound PrTi$_2$Al$_{20}$ is a quadrupolar Kondo lattice system that exhibits quadrupolar ordering due to the non-Kramers $Γ_3$ ground doublet and has strong hybridization between $4f$ and conduction electrons. Our study using high-purity single crystal reveals that PrTi$_2$Al$_{20}$ exhibits type-II superconductivity at $T_{\rm c} = 200$ mK in the nonmagnetic ferroquadrupolar state. The superconducting critical temperature and field phase diagram suggests moderately enhanced effective mass of $m^*/m_0 \sim 16$.

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Akito Sakai, Kentaro Kuga, Satoru Nakatsuji. 2012-07-07. Superconductivity in the Ferroquadrupolar State in the Quadrupolar Kondo Lattice PrTi$_2$Al$_{20}$. https://doi.org/10.1143/jpsj.81.083702

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