Demystifying science: What is magnetic cooling?

Physicists at the University of Basel, Switzerland, have recently succeeded in cooling a nanoelectronic chip to a temperature lower than 3 millikelvin. Absolute zero is 0 kelvin or -273.15°C and the closer they get to this limit, the better the chances of conducting experiments at the quantum level and observing entirely new physical phenomena. The recent cooling is the best yet achieved and for that the researchers employed a technique called magnetic cooling. With this, they were able to cool the electrical connections as well as the chip itself. Magnetic cooling is based on the fact that a system can cool down when an applied magnetic field is ramped down while any external heat flow is avoided. Before ramping down, the heat of magnetisation needs to be removed with another method to obtain efficient magnetic cooling. — Science Daily