Hacker News Reader

They probably have a dilution refrigerator. It's a pretty standard piece of equipment, and can achieve millikelvin level temperatures, far lower than the 3 Kelvin microwave background.

http://en.wikipedia.org/wiki/Dilution_refrigerator

There are other, more sophisticated methods of cooling, which can go even lower in temperature.

View on HN

Back when I was an undergrad at MIT I was a solder monkey for a group that used a dilution refrigerator with a very similar sort of setup, also trying to use current in niobium loops as qbits. However, IIRC we were only able to reach temperatures in the 100mK range, whereas the article claims this group is using temperatures less than 1mK. So I think they would probably have to be using something on top of the dilution refrigerator to get that low.

http://en.wikipedia.org/wiki/Magnetic_refrigeration

Dilution refrigerators have their limits, especially when you're trying to cool a complex experiment with a lot of wires and fibers going into it (they all bring in heat). I've seen magnetic refrig units stuck inside of helium cryostats to give them the extra oomph to get such experiments down to millikelvin levels.

Reply on news.ycombinator.com