Investigation of superconducting gap of high-entropy telluride AgInSnPbBiTe5

Asato Seshita; Hirotaka Okabe; Riad Kasem; Yuto Watanabe; Jumpei G. Nakamura; Shoichiro Nishimura; Kensei Terashima; Ryo Matsumoto; Yoshihiko Takano; Aichi Yamashita; Masaki Fujita; Yoshikazu Mizuguchi

arXiv · 2410.06548

Investigation of superconducting gap of high-entropy telluride AgInSnPbBiTe5

Asato Seshita·Hirotaka Okabe·Riad Kasem·Yuto Watanabe·Jumpei G. Nakamura·Shoichiro Nishimura·Kensei Terashima·Ryo Matsumoto·Yoshihiko Takano·Aichi Yamashita·Masaki Fujita·Yoshikazu Mizuguchi

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Abstract

We performed transverse-field muon spin relaxation/rotation (TF-{\mu}SR) on a high-entropy-type (HE-type) superconductor AgInSnPbBiTe5. The emergence of bulk superconducting states was confirmed from magnetic susceptibility, specific heat, and {\mu}SR. The superconducting gap 2{\Delta}(0) estimated from {\mu}SR was clearly larger than that expected from conventional weak-coupling phonon-mediated model, suggesting the strong-coupling nature of superconductivity. In addition, a long penetration depth of 3.21(7) {\mu}m was obtained. The strong-coupling nature of superconductivity and the long penetration depth are similar to the trends observed in the other HE-type superconductors (HE alloys and transition-metal zirconides), which may be universal feature of HE-type superconductors.

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Asato Seshita, Hirotaka Okabe, Riad Kasem, Yuto Watanabe, Jumpei G. Nakamura, Shoichiro Nishimura, Kensei Terashima, Ryo Matsumoto, Yoshihiko Takano, Aichi Yamashita, Masaki Fujita, Yoshikazu Mizuguchi. 2024-10-09. Investigation of superconducting gap of high-entropy telluride AgInSnPbBiTe5. https://arxiv.org/abs/2410.06548

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