IBM crams a ‘bit’ of data into atom-sized hard drive

Breakthrough achieved via special microscope that allows magnetic atoms to be manipulated and placed just one nanometre apart – one-millionth the width of a pinhead


Last night, IBM announced it had created the world’s smallest magnet using a single atom, and stored one bit of data on it. A hard drive currently needs 100,000 atoms to store a bit. The New York-based company has made a breakthrough in nanotechnology that will drastically change the form factor of the hard drive as we know it.

IBM hard drive atom
A view through IBM’s scanning tunneling microscope of a single atom of Holmium, a rare earth element used as a magnet to store one bit of data. The nanotechnology breakthrough allows reading and writing of data on two such atoms while they are seperated by only nanometre, which is one millionth the width of a pin head

The example cited by IBM in its press release offers a tantalising possibility. You could fit 35 million songs – the entire iTunes library – on a device the size of a credit card. If you average 10MB per track, that equates to 350,000 GB. Even if using the current standard bearer – Seagate’s upcoming 60 TB SSD hard drive – you’d still need a big backpack to hold five of these.

IBM hard drive
Seagate’s upcoming 60GB SSD, currently the world’s largest SSD hard drive. Data contained in five of these could fit in a credit card-sized object following IBM’s breakthrough (Picture:

“Magnetic bits lie at the heart of hard-disk drives, tape and next-generation magnetic memory,” said Christopher Lutz, Lead Nanoscience Researcher at IBM Research – Almaden in San Jose, California. “We conducted this research to understand what happens when you shrink technology down to the most fundamental extreme – the atomic scale.” 

The science behind an atom-size hard drive

An atom is the smallest unit of common matter. Scientists used electrical current to read and write a single bit of information on this unit. They demonstrated that two magnetic atoms could be written and read independently even while separated by just one nanometre. For scale, imagine the head of a pin – a nanometre is one millionth the width of this. This tight spacing could eventually yield magnetic storage 1,000 times denser than today’s hard disk drives and solid state memory chips. Future nanostructures built with control over the position of each atom could allow us to store 1,000 times more information in the same space, making data centres, computers and personal devices radically smaller and more powerful.


IBM hard drive microscope
Christopher Lutz of IBM Research with the scanning tunneling microscope used to store data on a single atom magnet

The study was published in the peer-reviewed journal, Nature.

The IBM scientists used a scanning tunneling microscope (STM). The device, which won the company a 1986 Nobel Prize for Physics, built and measured isolated single-atom bits using the holmium atoms. The custom microscope operates in extreme vacuum conditions to eliminate interference by air molecules and other contamination. The microscope also uses liquid helium for cooling, which allows the atoms to retain their magnetic orientations long enough to be written and read reliably.

Future plans for the STM include investigations into the potential of using individual magnetic atoms to perform quantum information processing.