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arXiv · 2605.20966

Multiple Superconducting Phases in Palladium Deuteride Induced by Nuclear-Spin Isotope Effect

Ryoma Kato·Ten-ichiro Yoshida·Riku Iimori·Masanobu Shiga·Yuji Inagaki·Takashi Kimura·Koichiro Ienaga·Tatsuya Kawae
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Abstract

We study the superconducting properties of high-quality PdD$_{x}$ films. The resistivity shows a sharp drop at $T$ $\sim$1.7 K, marking the superconducting transition. However, a finite resistivity persists and vanishes at $\sim$0.6 K. The temperature and magnetic-field dependences of the resistivity exhibit multiple anomalies within the superconducting state, revealing distinct superconducting phases. Such anomalies are absent in PdH$_{x}$ films. These results demonstrate a clear qualitative difference between the superconducting phase diagrams of PdD$_{x}$ and PdH$_{x}$, highlighting the role of nuclear-spin isotope effects.

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Ryoma Kato, Ten-ichiro Yoshida, Riku Iimori, Masanobu Shiga, Yuji Inagaki, Takashi Kimura, Koichiro Ienaga, Tatsuya Kawae. 2026-05-20. Multiple Superconducting Phases in Palladium Deuteride Induced by Nuclear-Spin Isotope Effect. https://arxiv.org/abs/2605.20966

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