Making a Bigger Chill With Magnets

LOS ANGELES—Refrigerator magnets are best known for holding shopping lists and old postcards onto refrigerator doors. But in a few years, much more powerful magnets could be the key to keeping food cold in so-called magnetocaloric refrigerators, which would be more energy efficient and less polluting than standard models. Now a new class of magnetocaloric materials, announced here last week at a meeting of the American Physical Society, could make these magnetic refrigerators more practical and versatile.