40 K single-stage coaxial pulse tube cryocoolers

Several 40 K single-stage coaxial high frequency pulse tube cryocoolers (PTCs) have been developed to provide reliable and low-noise cooling for GaAs/AlGaAs Quantum-Well infrared photodetectors (QWIPs). The inertance tubes together with the gas reservoir become the only phase shifter to guarantee the required long-term stability. The mixed regenerator consisting of three segments has been developed to enhance the overall regenerator performance. At present, the cooler prototype has achieved a no-load temperature of 29.7 K and can typically provide 860 mW cooling at 40 K with 200 W electric input power rejecting at 300 K. The performance characteristics such as the temperature stability and ambient temperature adaptability are also presented.

► Single stage coaxial pulse tube cryocoolers without the double-inlet reach a no-load temperature of 29.7 K. ► The mixed regenerator consisting of three segments has been developed to enhance the overall regenerator performance. ► The inertance tubes together with the gas reservoir as the only phase shifter guarantee the stability. ► They provide 860 mW at 40 K with 200 W of electric input power rejecting at 300 K. ► They have the potential to cool GaAs/AlGaAs QWIPs.