Beschreibung:
<jats:p>The integrated multiple mixing chamber is a simple and novel component that replaces the conventional single mixing chamber in the He3 circulating dilution refrigerator. The chamber incorporates or ’’integrates’’ many mixing chambers in a single block of low thermal conducting material; the mixing chambers are interconnected in tandem by internal channels and by internal holes. Thermal isolation between adjacent mixing chambers is achieved through the Kapitza boundary resistance between the helium liquids and the walls of each mixing chamber, and through the low thermal conductance of the body material. Theoretically, the integrated chamber is expected to provide a reduction in temperature by a factor of three to ten over the minimum temperature of a single mixing chamber, depending upon the magnitude of the heat leaks and the He3 circulation rate. Experimentally, temperatures of 4.8 mK have been observed as compared to a 12 mK minimum temperature obtained in a single mixing chamber.</jats:p>