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arXiv · 2408.14824

Nonvolatile magneto-thermal switching driven by vortex trapping in commercial In-Sn solder

Poonam Rani·Takumi Murakami·Yuto Watanabe·Hossein Sepehri-Amin·Hiroto Arima·Aichi Yamashita·Yoshikazu Mizuguchi
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Abstract

Magneto-thermal switching (MTS) is a key technology for efficient thermal management. Recently, large MTS with nonvolatility has been observed in Sn-Pb solders [H. Arima et al., Commun. Mater. 5, 34 (2024)] where phase separation, different superconducting transition temperature (Tc) of Sn and Pb, and magnetic-flux trapping are the causes of the nonvolatile MTS. To further understand the mechanism and to obtain the strategy for enhancing switching ratio, exploration of new phase-separated superconductors with nonvolatile MTS is needed. Here, we show that the In52-Sn48 commercial solder is a phase-separated superconducting composite with two Tc and traps vortices after field cooling. A clear signature of nonvolatile MTS was observed at T = 2.5 K. From specific heat analyses, we conclude that the vortices are mainly trapped in the lower-Tc phase (γ-phase) after field cooling, which is the evidence that vortex trapping also works on achieving nonvolatile MTS in phase-separated superconducting composites.

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Poonam Rani, Takumi Murakami, Yuto Watanabe, Hossein Sepehri-Amin, Hiroto Arima, Aichi Yamashita, Yoshikazu Mizuguchi. 2024-08-27. Nonvolatile magneto-thermal switching driven by vortex trapping in commercial In-Sn solder. https://doi.org/10.35848/1882-0786%2Fadb6ee

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