Absence of Tc-Pinning Phenomenon Under High Pressure in High-Entropy REO0.5F0.5BiS2 Layered Superconductor

Yoshikazu Mizuguchi; Kazuki Yamane; Ryo Matsumoto; Kazuhisa Hoshi; Aichi Yamashita; Akira Miura; Yuki Nakahira; Hirokazu Kadobayashi; Saori I. Kawaguchi; Yoshihiko Takano

arXiv · 2308.04081

Absence of Tc-Pinning Phenomenon Under High Pressure in High-Entropy REO0.5F0.5BiS2 Layered Superconductor

Yoshikazu Mizuguchi·Kazuki Yamane·Ryo Matsumoto·Kazuhisa Hoshi·Aichi Yamashita·Akira Miura·Yuki Nakahira·Hirokazu Kadobayashi·Saori I. Kawaguchi·Yoshihiko Takano

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Abstract

Recently, robustness of superconductivity (transition temperature, Tc) under high pressures has been observed in high-entropy alloy (HEA), bcc-type Ti-Zr-Hf-Nb-Ta, and HEA-type compounds (Ag,In,Sn,Pb,Bi)Te with a NaCl-type structure. Since those materials have three-dimensional crystal structure, investigation on the pressure dependence of Tc of low-dimensional materials is needed to understand the phenomena. Here, we investigated the superconducting properties and the crystal structure of BiS2-based layered system REO0.5F0.5BiS2. Although the robustness of Tc was induced in MTe with increasing M-site configurational entropy, the increase in RE-site configurational entropy does not induce robustness of Tc under high pressures in REO0.5F0.5BiS2. The crystal structure of HEA-type REO0.5F0.5BiS2 was confirmed as monoclinic P21/m, which is the same space group as the zero-entropy counterpart LaO0.5F0.5BiS2. The results suggest that an increase in configurational entropy at blocking layers do not affect crystal structure and superconducting properties under high pressures in the BiS2-based layered system.

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Yoshikazu Mizuguchi, Kazuki Yamane, Ryo Matsumoto, Kazuhisa Hoshi, Aichi Yamashita, Akira Miura, Yuki Nakahira, Hirokazu Kadobayashi, Saori I. Kawaguchi, Yoshihiko Takano. 2023-08-08. Absence of Tc-Pinning Phenomenon Under High Pressure in High-Entropy REO0.5F0.5BiS2 Layered Superconductor. https://arxiv.org/abs/2308.04081

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