Estimation of Gr\"uneisen Parameter of Layered Superconductor LaO0.5F0.5BiS2-xSex (x = 0.2, 0.4, 0.6, 0.8, 1.0)

Fysol Ibna Abbas; Kazuhisa Hoshi; Yuki Nakahira; Miku Yoshida; Aichi Yamashita; Hiroaki Ito; Akira Miura; Chikako Moriyoshi; Chul-Ho Lee; Yoshikazu Mizuguchi

arXiv · 2208.11880

Estimation of Gr\"uneisen Parameter of Layered Superconductor LaO0.5F0.5BiS2-xSex (x = 0.2, 0.4, 0.6, 0.8, 1.0)

Fysol Ibna Abbas·Kazuhisa Hoshi·Yuki Nakahira·Miku Yoshida·Aichi Yamashita·Hiroaki Ito·Akira Miura·Chikako Moriyoshi·Chul-Ho Lee·Yoshikazu Mizuguchi

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Abstract

The superconducting properties and structural parameters, including the Gr\"uneisen parameter ({\gamma}G), of the BiCh2-based (Ch: S, Se) layered superconductor LaO0.5F0.5BiS2-xSex were investigated. The superconducting transition temperature (Tc) increased with increasing Se concentration (x), and bulk superconductivity was induced by Se substitution. {\gamma}G exhibited a larger value when x greater than 0.4, where the superconducting properties were improved. These results suggest that the increase of lattice anharmonicity is preferable for superconductivity in LaO0.5F0.5BiS2-xSex. The discussion includes data for related superconductors REO0.5F0.5BiS2 (RE = Pr, Nd), where a positive correlation between {\gamma}G and Tc is revealed for Se-poor samples. In addition, specific heat analyses suggest the presence of a low-energy optical phonon mode for LaO0.5F0.5BiS2-xSex.

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Fysol Ibna Abbas, Kazuhisa Hoshi, Yuki Nakahira, Miku Yoshida, Aichi Yamashita, Hiroaki Ito, Akira Miura, Chikako Moriyoshi, Chul-Ho Lee, Yoshikazu Mizuguchi. 2022-08-25. Estimation of Gr\"uneisen Parameter of Layered Superconductor LaO0.5F0.5BiS2-xSex (x = 0.2, 0.4, 0.6, 0.8, 1.0). https://arxiv.org/abs/2208.11880

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