Before they switched to moviemaking, the team was working to develop technology for the memory of the future. In 2012, they used the STM to position individual iron atoms on a copper substrate coated with copper nitride. By adjusting the voltage applied to the STM probe, they were able to switch the magnetic orientation of all twelve individual atoms. All 12 atoms switch direction together. The checkerboard pattern of blue and white is the measured direction of the magnetism, which alternates from atom to atom to form an antiferromagnet. “They’re really like classical magnets in that they sit there holding their direction of magnetization for a long time,” says Lutz. “We probe them using spin polarized currents from the STM tip in order to determine which way they’re pointed.” The result was a 12-atom nonvolatile memory bit.