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arXiv · 2202.09067

Precise magnetization measurements down to 500 mK using a miniature 3He cryostat and a closed-cycle 3He gas handling system installed in a SQUID magnetometer without continuous-cooling functionality

Kazutoshi Shimamura·Hiroki Wajima·Hayato Makino·Satoshi Abe·Yoshinori Haga·Yoshiaki Sato·Tatsuya Kawae·Yasuo Yoshida
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Abstract

We have conducted precise magnetization measurements down to 0.5 K with a miniature 3He cryostat and a closed-cycle 3He gas handling system for a commercial superconducting quantum interference device magnetometer [Magnetic Property Measurement System (Quantum Design)]. The gas handling system contains two sorption pumps filled with granular charcoals. We pressurize 3He gas up to ambient pressure for the liquification at 3 K and then pump the vaper for cooling. The lowest sample temperature is ~ 0.5 K and it can persist for 34 hours. We demonstrate the performance of the system by observing the Meissner effect of aluminum below the superconducting transition temperature ~ 1 K. We also measured the magnetization curve of the heavy fermion superconductor CeCoIn5 resulting in successful observation of the lower critical field at 0.5 K.

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Kazutoshi Shimamura, Hiroki Wajima, Hayato Makino, Satoshi Abe, Yoshinori Haga, Yoshiaki Sato, Tatsuya Kawae, Yasuo Yoshida. 2022-02-18. Precise magnetization measurements down to 500 mK using a miniature 3He cryostat and a closed-cycle 3He gas handling system installed in a SQUID magnetometer without continuous-cooling functionality. https://doi.org/10.35848/1347-4065%2Fac5bb0

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