IBM Turns An Atom Into A Nano-Scale Hard Drive
By now it's a truism that data storage keeps getting smaller and smaller, but even with that knowledge IBM's latest advance is still jaw-dropping. Researchers at the company have managed to store data on a single atom, by turning it into the world's tiniest magnet. Admittedly, its single bit capacity isn't going to replace the USB drive in the bottom of your bag, but IBM says the potential is huge.
"We conducted this research to understand what happens when you shrink technology down to the most fundamental extreme," Christopher Luzt, lead nano science researcher at IBM Research explains, "the atomic scale." Lutz and his San Jose, CA-based team used another piece of groundbreaking technology to achieve the unusual storage. The company had already made a scanning tunnel microscope that could see the data-storing atom in action.
Starting with a single atom, the data was written by passing an electrical current through it. What makes the scanning tunneling microscope (STM) special – and helped it win a Noble Prize for Physics back in 1986 – is that it allows single atoms of Holmium to retain their magnetic orientation while still being examined. That requires liquid helium for cooling, as well as an extreme vacuum.
Previous research had maxed out on 3-12 atoms as the smallest individually-addressable bistable magnetic bits. Luzt and his team showed that not only could that be pared down to just one atom, the magnetic information also proved stable over many hours. Equally important, two magnetic atoms could be independently written and read, they proved, despite only a nanometer of distance between them.
Altogether, it opens the door to brand new, extremely high-density storage. Current hard drives rely on approximately 100,000 atoms to store a single bit, but IBM Research's findings suggest future drives could shrink considerably while still holding more data. Indeed, you could potentially fit the 35m song iTunes library onto a drive the size of a credit card, it's suggested.
It'll take considerable development to get to such a stage, mind. For a start, drive manufacturers would need to successfully figure out how to precisely control the position of every atom in a nanostructure. That's several levels of precision higher than currently expected from modern storage.
Nonetheless, the possible benefits are huge – or, ironically, tiny. Data centers dramatically smaller than their current building-filling forms, or smartphones and tablets that have many terabytes of local capacity. When that might happen is uncertain, but demonstrating that single-atom magnetic memory is at least possible is a good first step to getting there.
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