Capillary flow impedances for the dilution refrigerator

✍ Scribed by W. Wei; R. Rosenbaum

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 153 KB
• Volume: 29
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(89)90018-0

✦ Synopsis

5 mm or longer crystal with a nonconducting epoxy such as Stycast* and place it on a small sheet of polyethylene (such as Glad Cling Wrap) t to cure. To make a device out of polycrystalline material, thoroughly mix one part of epoxy with two parts of caesium nitrate. Compress the mixture between two flat plates covered with polyethylene to a thickness of approximately 1 mm. Small washers may be used as spacers. A total premixed volume of approximately 3 cm 3 will make a disc 1 mm thick and 4 cm diameter. Exact measurements are not necessary. After the epoxy has cured for 12-24 h at room temperature or 30 rain at 90°C, separate the plates and peel off the polyethylene. The pyroelectric disc may now be cut or drilled as desired. Several discs may be used to form a collector.

The discs are suspended in dewars from strings to collect impurities or ice crystals as they form. The collector is withdrawn periodically to remove the impurities. The frequency of removal depends on the rate of ice build-up;