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arXiv · 2405.09129

Aging Effects on Superconducting Properties of BiS2-Based Compounds: First-12-Year Restudy

Poonam Rani·Rajveer Jha·V. P. S. Awana·Yoshikazu Mizuguchi
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Abstract

Decomposition of superconductors sometimes becomes crucial when studying essential physical properties of the superconductors. For example, the cuprate superconductor YBa2Cu3O7-d decomposes by long-time air exposure. In this study, we investigate the aging effects on superconducting properties of BiS2-based superconductors Bi4O4S3 and LaO0.5F0.5BiS2, both were first synthesized in 2012, using their polycrystalline samples synthesized several years ago. We find that 12-year-old Bi4O4S3 samples exhibit bulk superconductivity with a slight degradation of the superconducting transition temperature (Tc) of 0.2 K. For a high-pressure-synthesized LaO0.5F0.5BiS2 sample, clear decrease in Tc is observed, which suggests that high-pressure strain is reduced by aging.

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Poonam Rani, Rajveer Jha, V. P. S. Awana, Yoshikazu Mizuguchi. 2024-05-15. Aging Effects on Superconducting Properties of BiS2-Based Compounds: First-12-Year Restudy. https://arxiv.org/abs/2405.09129

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