COMPACT fridges that chill using magnets are on every physicist’s wish list, but now they have moved a step closer to our kitchens, as two teams unveiled the smallest magnetic refrigerators so far. The chillers don’t need to use coolants that damage the environment. And they promise to be more versatile and efficient than conventional fridges, leading to potential energy savings worth $10 billion every year in the US alone.
Magnetic refrigerators were first suggested in 1926. They exploit “magnetocaloric” metals, in which the atoms act like tiny bar magnets pointing in random directions. When they are placed in a…
