[jessriedel]

Great, then we both have physics PhDs, and you'll know that none of that equipment has, or easily could be, sufficiently miniaturized, which is the topic of discussion ("extremely small cryocooler"). You can't put nested closed dewers of liquid nitrogen and helium on a O(1 mm^2) microchip, and the reason is exactly what I said: it will warm up too fast.

[Calloutman]

Ah, you're totally right. I misread the OP. Sorry.

[jessriedel]

No problem :)

[extropy]

What's wrong with attaching said microchip to a piece of copper for increased size? Genuinely curious.

To be useful in a data center you could cool a slab of copper the size of a fridge and surface mount thousands of chips on it.

[jessriedel]

The topic is cooling small objects so that personal electronics (e.g., your phone) can compete with datacenters. Cold at scale (i.e., in datacenters) is comparatively easy.