3He/ 4He dilution refrigerator with Gifford-McMahon precooling

Abstract

We present data and constructional details of a 3He/ 4He dilution refrigerator where a commercial two-stage Gifford-McMahon closed cycle refrigerator (Leybold RGD 510) precools the dilution unit, and thus this refrigerator does not require any external supply of liquid nitrogen or helium. The lowest temperature reached in the mixing chamber was 42 mK at a 3He flow rate of 1 × 10 −4 mol s −1.