Two new types of pulse tube refrigerators with optimized cooling power of 6
W at 77 K have been designed and fabricated. Experiments show that vibrati
on of the pulse tube refrigerators is at least an order of magnitude smalle
r than that of Stirling coolers. Two microwave devices, a HTS cavity and a
HTS miniature lumped band-stop filter, were integrated with the refrigerato
rs and operated successfully, which demonstrated the potential application
of these integrated devices and the refrigerator as practical HTS sub-syste
ms.