The current method of manufacturing carbon nanotubes—in essence rolled up sheets of graphene—is unable to allow complete control over their diameter, length and type. This problem has recently been solved for two of the three different types of nanotubes, but the third type, known as 'zigzag' nanotubes, had remained out of reach. Researchers with Japan's National Institutes of Natural Sciences (NINS) have now figured out how to synthesize the zigzag variety.