Cold-Cycle Dilution Refrigerator (CCDR)

Abstract - 9711304 Escherichson，John G. 主要研究者建议开发一种冷循环稀释制冷机（CCDR），用于100 mK以下的冷却。 传统的稀释制冷机在低温下将3 He稀释成4 He以实现亚开尔文冷却。 该过程的低效率与3 He组分从0.6 K到室温并再次返回的循环有关。 在所提出的设计中，压缩机在0.25 K下（而不是在传统的稀释制冷机中的300 K下）蒸馏并泵送mexture的3 He组分，并将3 He组分直接返回到混合室。 使用超流斯特林制冷机将压缩机维持在0.25 K。 该项目还将涉及低损耗、低温压缩机阀门的开发。 由此产生的CCDR将具有提高的效率、小尺寸和成本。

Abstract - 9711304 Brisson, John G. The principal investigator proposes to develop a cold-cycle dilution refrigerator (CCDR) for cooling below 100 mK. Conventional dilution refrigerators dilute 3He into 4He at a low temperature to achieve sub-Kelvin cooling. An inefficiency of this process is related to the circulating of the 3He component from 0.6 K to room temperature and back again. In the proposed design, the compressor distills and pumps the 3He component of the mexture at 0.25 K (rather than at 300 K in conventional dilution refrigerators) and directly returns the 3He component to the mixing chamber. The compressor will be maintained at 0.25 K using a superfluid Stirling refrigerator. The project will also involve the development of low-loss, low-temperature compressor valves. The resulting CCDR will have improved efficiency, small size and cost.