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arXiv · 2203.11566

Lattice Anharmonicity in BiS2-Based Layered Superconductor RE(O,F)BiS2 (RE = La, Ce, Pr, Nd)

Fysol Ibna Abbas·Kazuhisa Hoshi·Aichi Yamashita·Yuki Nakahira·Yosuke Goto·Akira Miura·Chikako Moriyoshi·Yoshihiro Kuroiwa·Kensei Terashima·Ryo Matsumoto·Yoshihiko Takano·Yoshikazu Mizuguchi
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Abstract

We studied Gr\"uneisen parameter ({\gamma}G) to investigate lattice anharmonicity in a layered BiS2-based superconductor system REO1-xFxBiS2 (RE = La, Ce, Pr, Nd), where in-plane chemical pressure was tuned by substituting the RE elements. With increasing in-plane chemical pressure, bulk modulus remarkably increases, and a high {\gamma}G is observed for RE = Nd. The dependence of {\gamma}G on in-plane chemical pressure exhibits a good correlation with Tc, and a higher Tc is achieved when {\gamma}G is large for RE = Nd. In addition, {\gamma}G shows a slight decrease by a decrease of F concentration (x) in REO1-xFxBiS2. Our results show that the anharmonic vibration of Bi along the c-axis is present in REO1-xFxBiS2, and the enhancement of the anharmonicity is positively linked to superconducting Tc and pairing mechanisms.

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Fysol Ibna Abbas, Kazuhisa Hoshi, Aichi Yamashita, Yuki Nakahira, Yosuke Goto, Akira Miura, Chikako Moriyoshi, Yoshihiro Kuroiwa, Kensei Terashima, Ryo Matsumoto, Yoshihiko Takano, Yoshikazu Mizuguchi. 2022-03-22. Lattice Anharmonicity in BiS2-Based Layered Superconductor RE(O,F)BiS2 (RE = La, Ce, Pr, Nd). https://doi.org/10.7566/jpsj.91.074706

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