From computers to credit cards to cloud servers, today's technology relies on magnets to hold encoded data in place on a storage device. But a magnet's size limits storage capacity; even a paper-thin magnet takes up space that could be better used for encoding information. Now, for a study published in Nature Communications, researchers have engineered a magnet among the world's thinnest—a flexible sheet of zinc oxide and cobalt just one atom thick. "That means we can store larger amounts of data using the same amount of materials," says University of California, Berkeley, engineer Jie Yao , the study's senior author.