长期以来,人们要得到液体氦(He4)温度以下(1K)直到毫开(mK,即千分之一开尔文)范围的温度,只有用顺磁盐绝热去磁的方法.这种方法不能连续制冷,只能在较短的时间内维持所得到的低温,冷却能力也很低,给实验工作带来了很大的限制.五十年代末期,由于从核反应中能够得到较多He4的同 For a long time, the only way to demagnetize with paramagnetic salt is to obtain the temperature below (1K) below the temperature of the liquid He (Helium) (Hertz), and to demagnetize it with paramagnetic salts , Only to maintain the resulting low temperature in a relatively short period of time, cooling capacity is also very low, to experimental work has brought great limitations.In the late fifties, because from the nuclear reaction can get more He4