The forthcoming generation of cosmic microwave background polarization observatories is developing large format detector arrays which will operate at 100 mK. Given the volume of detector wafers that will be required, fast-cooldown 100 mK test cryostats are increasingly needed. A miniature dilution refrigerator (MDR) has been developed for this purpose and is reported. The MDR is precooled by a double-stage $${^3}\mathrm{He}$$ 3 He – $${^4}\mathrm{He}$$ 4 He Chase Research Cryogenics sorption refrigerator. The test cryostat based on this MDR will enable fast cooldown to 100 mK to support rapid feedback testing of detector wafers fabricated for the Simons Observatory. The MDR has been designed to provide a 100 mK stage to be retrocompatible with existing CRC10 sorption coolers, reducing the base temperature from 250 mK for the new generation of detectors. Other 250 mK cryostats can be retrofitted in the same way. This configuration will meet the cryogenic requirements for single-wafer testing, providing 5–10 $$\upmu \mathrm{W}$$ μ W of cooling power at 100 mk for over 8 h. The system operates in a closed cycle, thereby avoiding external gas connections and cold o-rings. No moving parts are required, with the system operated entirely by heaters.

中文翻译：

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用于快速冷却 100 mK 探测器晶圆测试低温恒温器的闭环微型稀释冰箱

下一代宇宙微波背景极化天文台正在开发工作在 100 mK 的大尺寸探测器阵列。考虑到所需的探测器晶圆数量，越来越需要快速冷却 100 mK 测试低温恒温器。为此目的开发了一种微型稀释冰箱 (MDR) 并进行了报道。MDR 由双级 $${^3}\mathrm{He}$$ 3 He – $${^4}\mathrm{He}$$ 4 He Chase Research Cryogenics 吸附冰箱预冷。基于此 MDR 的测试低温恒温器将能够快速冷却至 100 mK，以支持对为西蒙斯天文台制造的探测器晶片进行快速反馈测试。MDR 设计用于提供 100 mK 级以与现有的 CRC10 吸附冷却器兼容，将新一代探测器的基础温度从 250 mK 降低。其他 250 mK 低温恒温器可以用同样的方式改装。这种配置将满足单晶片测试的低温要求，在 100 mk 下提供 5–10 $$\upmu \mathrm{W}$$ μ W 的冷却功率超过 8 小时。该系统在封闭循环中运行，从而避免了外部气体连接和冷 O 形圈。不需要移动部件，系统完全由加热器操作。