12 = 1 (or 0)

IBM scientists have used a scanning tunnelling microscope to make a magnetic storage device from only twelve atoms. By using antiferromagnetism to limit external magnetic fields, the IBM group have been able to encode a bit of data in just 12 iron atoms. They then placed eight of the 12-atom bits side by side creating a byte of data made of 96 atoms. Because no magnetic field strayed from each cluster of 12 atoms, the bits could be placed very close, creating a byte 100 times as dense as those typically used in today's hard drives. Apparently using less than twelve atoms is a problem. Smaller numbers of atoms are too unstable to act as bits, without neighbours to interact with and stabilise them, the atoms behaved like quantum objects that existed in multiple spin states at once.