无磁非金属微型同轴脉冲管制冷机的设计分析

分析了脉冲管制冷机系统中存在的主要干扰源 ,并给出了其相应的解决方法 ,在此基础上设计并制作了一台无磁非金属微型同轴脉冲管制冷机。常规脉冲管制冷机中由磁性或金属材料所产生的电磁干扰和感应涡流 ,是将微型脉冲管制冷机应用到高灵敏度高温超导量子干涉仪冷却上的最大障碍。作者采用一系列无磁非金属电绝缘的材料完全替代脉冲管中的磁性或金属材料 ,以实现脉冲管制冷机的低电磁干扰化、甚至无电磁干扰化 ,并最终实现利用脉冲管制冷机 ,有效冷却包括高温超导量子干涉仪在内的对电磁干扰要求极严格的高温超导器件

ANALYSIS ON DESIGNING A NONMAGNETIC AND NONMETALLIC MINIATURE COAXIAL PULSE TUBE CRYOCOOLER

The main source of interference signals of a pulse tube cryocooler(PTC) system were analyzed in detail. The practicable solutions for minimizing them were found. Then a nonmagnetic and nonmetallic miniature pulse tube cryocooler was designed and fabricated. The biggest obstacles for cooling highly sensitive high-Tc SQUID by a miniature PCT was the electromagnetic interference and the induced eddy currents from the magnetic or metallic materials in a PTC system. All the magnetic or metallic ones in a PTC were gaven place to nonmagnetic, non-metallic and electronically insulating ones, so that the EMI and eddy currents from them could be mininized. The objective was supplying a nonmagnetic and nonmetallic PTC for the low-noise cooling of highly magnetic flux sensitive high-Tc superconductors including high-Tc SQUIDs.