Cryocooler with ambient temperature surge volume

A hybrid multistage cryocooler comprising:

• a first-stage expander having a first-stage expander outlet;
• a first-stage thermal interface;
• a second stage in communication with the first-stage expander outlet, via the first-stage thermal interface;
• a surge volume in communication with a second-stage expander, via the first-stage thermal interface;
• and
• an inertance tube coupling the surge volume to the first-stage thermal interface;
• wherein the surge volume is maintained at an ambient temperature;
• wherein a first end of the inertance tube is at the ambient temperature,
• wherein a second end of the inertance tube is at a first-stage temperature that is lower than the ambient temperature;
• wherein the first-stage expander is a Stirling expander;
• wherein the first-stage thermal interface is coupled to an expansion volume of the first-stage expander;
• and
• wherein the first-stage thermal interface is cantilevered off the expansion volume.

A method of cooling, comprising:

• providing a first-stage expander having a first-stage expander outlet;
• providing a first-stage thermal interface;
• providing a second-stage cooler in communication with the first-stage expander outlet, via the first-stage thermal interface;
• and
• coupling a surge volume in communication with the first-stage expander outlet and the second-stage cooler, via the first-stage thermal interface, wherein the coupling includes placing the surge volume such that the surge volume is maintained at an ambient temperature.