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arXiv · 2306.01239

Superconductivity at 12 K in La$_2$IOs$_2$: a 5d metal with osmium honeycomb layer

Hajime Ishikawa·Takeshi Yajima·Daisuke Nishio-Hamane·Shusaku Imajo·Koichi Kindo·Mitsuaki Kawamura
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Abstract

We discovered superconductivity at $T_c$ = 12 K in a layered compound La$_2$IOs$_2$ with osmium honeycomb network. Despite heavy constituent elements unfavorable for phonon mediated mechanism, $T_c$ is the highest among lanthanoid iodides made of lighter elements such as La$_2$IRu$_2$ with $T_c$ = 4.8 K. Electronic anomalies are observed below 60 K similar to those observed in La$_2$IRu$_2$ below 140 K. La$_2$IOs$_2$ is a layered 5d electron system providing a platform to investigate the interplay between the electronic anomaly, superconductivity, and strong magnetic field.

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Hajime Ishikawa, Takeshi Yajima, Daisuke Nishio-Hamane, Shusaku Imajo, Koichi Kindo, Mitsuaki Kawamura. 2023-06-02. Superconductivity at 12 K in La$_2$IOs$_2$: a 5d metal with osmium honeycomb layer. https://doi.org/10.1103/physrevmaterials.7.054804

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