很接近于绝对零度的1K以下的温区,一直受到物理学家的重视,很多领域的多种研究工作已被扩展到该温区[1].自1908年获得液He以来,已经有好几种方法被发展来获得 1K以下的温度.降低液 He4表面的蒸汽压可以方便地获得1K左右的温度,经过特别设计的He4恒温器甚至可以得到0.5-0.6K的温 Very close to the absolute temperature of 1K below the temperature zone, has been physicists attention, many fields of research work has been extended to this area [1]. Since the liquid He obtained in 1908, there are already several The method has been developed to obtain temperatures below 1 K. Reducing the vapor pressure on the He4 surface can easily achieve temperatures around 1 K and even a specifically designed He4 thermostat can achieve temperatures of 0.5-0.6 K