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.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.