3He/4He dilution refrigerator with pulse-tube refrigerator precooling Original Research Article

A dilution refrigerator is described which is precooled by a two-stage pulse-tube refrigerator and thus no cryoliquids are needed to operate this millikelvin cooler. The cool-down process from room temperature to a precooling temperature below 3 K is automatic, and operating the dilution refrigerator is convenient. It takes about two hours to condense the 3He/4He mash; with just a standard rotary pump to circulate the 3He in the dilution circuit and a very simple dilution unit we reached a final temperature of 15 mK.