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arXiv · 2503.10754

A continuously-cooled 3He/4He phase separation refrigerator

P. H. Kim·M. Hirschel·J. Suranyi·J. P. Davis
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Abstract

We present a novel cooling method that uses the phase separation and evaporative cooling of 3He to reach and continuously maintain sub-kelvin temperatures. While less complex than a dilution refrigerator, the system performs similarly to a continuous 3He cryostat but with a simpler design, a more efficient cooldown process, and a significantly smaller 3He requirement. Our prototype demonstrated a base temperature of 585 mK and 3 mW cooling power at 700 mK using just two gaseous liters of 3He. Lower temperatures could be expected in systems with improved heat exchangers and pumping efficiency.

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P. H. Kim, M. Hirschel, J. Suranyi, J. P. Davis. 2025-03-13. A continuously-cooled 3He/4He phase separation refrigerator. https://arxiv.org/abs/2503.10754

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