Self-contained cooling apparatus for achieving cyrogenic temperatures

A cryogenic cooling apparatus comprising:

• a vacuum container for containing an object to be cooled;
• at least one refrigerator for cooling the object, said refrigerator including a high-temperature cooling stage and a low-temperature cooling stage arranged at a predetermined distance from each other with a low-temperature cylinder interposed between the high-temperature cooling stage and the low-temperature cooling stage;
• and
• a thermal switch unit comprising,
• at least one high-temperature heat transfer member attached to said high-temperature cooling stage of said refrigerator,
• at least one low-temperature heat transfer member which is attached to said low-temperature cooling stage of said refrigerator and separated from said at least one high-temperature heat transfer member, and
• a sealed container, having no communication with an outside portion of said sealed container during an operation of said thermal switch unit and provided between said low-temperature cooling stage and said high-temperature cooling stage, for containing said at least one high-temperature heat transfer member, and a substance, heat conduction between said at least one high-temperature heat transfer member and said at least one low-temperature heat transfer member occurring via said substance when said substance is a gas.