8 October 2004 A miniature continuous adiabatic demagnetization refrigerator with compact shielded superconducting magnets
Author Affiliations +
Abstract
Cryogenic detectors for astrophysics depend on cryocoolers capable of achieving temperatures below ~ 100 mK. In order to provide continuous cooling at 50 mK for space or laboratory applications, we are designing a miniature adiabatic demagnetization refrigerator (MADR) anchored at a reservoir at 5 K. Continuous cooling is obtained by the use of several paramagnetic pills placed in series with heat switches. All operations are fully electronic and this technology can be adapted fairly easily for a wide range of temperatures and cooling powers. We are focusing on reducing the size and mass of the cooler. For that purpose we have developed and tested magnetoresistive heat switches based on single crystals of tungsten. Several superconducting magnets are required for this cooler and we have designed and manufactured compact magnets. A special focus has been put on the reduction of parasitic magnetic fields in the cold stage, while minimizing the mass of the shields. A prototype continuous MADR, using magnetoresistive heat switches, small paramagnetic pills and compact magnets has been tested. A design of MADR that will provide ~ 5 uW of continuous cooling down to 50 mK is described.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jean-Marc Duval, Jean-Marc Duval, Benjamin M. Cain, Benjamin M. Cain, Peter T. Timbie, Peter T. Timbie, "A miniature continuous adiabatic demagnetization refrigerator with compact shielded superconducting magnets", Proc. SPIE 5498, Millimeter and Submillimeter Detectors for Astronomy II, (8 October 2004); doi: 10.1117/12.552498; https://doi.org/10.1117/12.552498
PROCEEDINGS
10 PAGES


SHARE
Back to Top