Broadcasters have long used magnetic storage through the analog and digital eras. Now, researchers at IBM have significantly reduced the size of what it takes to hold ones and zeros to just 12 atoms.
The research, published recently in Science magazine, said IBM’s findings could lead to a new class of nanomaterials for memory chips and disk drives that will have greater storage capabilities and consume much less power.
This is significantly less than today’s disk drives, which use about one million atoms to store a single bit of information. The ability to manipulate matter by its most basic components—atom by atom—could lead to the basic information necessary to build smaller, faster and more energy-efficient devices.
While silicon transistor technology has become cheaper, denser and more efficient, fundamental physical limitations suggest this path of conventional scaling is unsustainable. Alternative approaches are needed to continue the rapid pace of computing innovation.
By beginning at the smallest unit of data storage, the atom, the IBM scientists demonstrated magnetic storage that is at least 100 times denser than today’s hard disk drives and solid-state memory chips. Future applications of nanostructures could allow people and businesses to store 100 times more information in the same space.
The IBM group created the smallest possible unit of magnetic storage by arranging two rows of six iron atoms on a surface of copper nitride. This closeness of atoms is possible because the cluster is antiferromagnetic. This is a rare quality in which each atom in the array has an opposed magnetic orientation—different from ferromagnetic materials like iron, nickel and cobalt where the atoms are magnetically aligned.
Antiferromagnetic materials are now key in two types of data storage products. The materials are essential for the manufacture of recording heads, which resemble phonograph needles and are used in the manufacture of hard disk drives. They are also used in a new type of memory chip known as spin-transfer-torque RAM, or STT-RAM. Some view this technology as a future competitor for DRAM and flash memory chips.
The research was done at IBM’s Almaden Research Center in San Jose, CA, led by Andreas Heinrich. “The chip industry will continue its pursuit of incremental scaling in semiconductor technology but, as components continue to shrink, the march continues to the inevitable end point: the atom,” Heinrich said. “We’re taking the opposite approach and starting with the smallest unit—single atoms—to build computing devices one atom at a time.”