Single-atom data storage has just been figured out

Most basic form of data, meet most basic form of matter.

  • Scientists have figured out how to store binary data in single atoms
  • Our technological ambitions require this kind of storage breakthrough
  • The new study may herald the start of a new age in computing

You've probably noticed that our appetite for storing data is ravenous. Just three or four years ago, we thought a terabyte of storage space was ridiculously capacious. Now, multi-terabyte storage is an everyday thing. And it's not just the data we want to stash away that we're having trouble handling. It's also the bits coursing through our processors and the power those straining processors require. We're reaching the limits of our hardware, so only a breakthrough in efficiency that packs data into a much tinier form than it currently inhabits could break through the wall we've been rapidly approaching.

Consider this. The essential smallest building block of data is a binary bit, a simple two-way switch set to either 0 or 1. (Eight bits equal a byte, and strings of bytes represent some mathematical value or other.) The smallest physical thing in the universe is the atom. Could we possibly store a bit on an atom? Scientists from the Radboud University in the Netherlands have just published research that presents how it can be done.

"Computers have reached fundamental limitations as to how much better they can get, creating a huge demand in materials research for alternatives. Modern computers use a lot of electricity, currently demanding more than 5 percent of the world's electricity. Fundamental science says we can gain a lot more in energy efficiency. We are focusing on a very basic component of modern computers: a bit of memory. We use atoms, because they are the smallest unit of matter and also enable us to further understand the fundamental science behind their behavior. Our current question: how can we store information within a single atom and how stable can we make that piece of information?" — Brian Kiraly, first author of the new research

The battle against constant spinning

An especially vexing problem is coercing single atoms into resting in a binary — 0 or 1 — state, because atoms want to spin. "What defines a permanent magnet is that it has a north and a south pole, which remains in the same orientation", according to co-author Alexander Khajetoorians, "But when you get down to a single atom, the north and south pole of the atom start to flip and do not know what direction they should point, as they become extremely sensitive to their surroundings. If you want a magnetic atom to hold information, it cannot flip."

(MandriaPix/Shutterstock)

Orbiting a solution

The electrons in a magnetized atom orbit its nucleus. They also spin on their own axes, much like the Earth spins as it orbits around the sun. The rate at which they spin is called their "spin angular momentum" and it produces the atom's magnetic charge. Electrons that share a similar spin angle momentum travel together around the nucleus in bands, called "orbitals." The further away they are from nucleus, the higher the electrons' spin angular momentum and the greater the charge each orbital produces. The speed at which each orbital group goes around the nucleus is called its "orbital angular momentum."

(Veronika Vieira)

Going binary

Previous efforts to use magnetized atoms as storage have focused on the spin angular momentum, such as the Swiss team from Ecole Polytechnique Federale de Lausanne who announced in early September that over the last couple of years they'd gotten magnetized atoms of holmium to stay put, but only in extreme cold up to 45 Kelvin. (That's a chilling -233.15 Celsius, though it counts as hot to atoms.)

The Radboud researchers took another tack. "Instead of this spin angular momentum, which previous researchers have used, we figured out a way to make an energy difference between a few of the orbitals of the cobalt atom and now use the orbital angular momentum for our atomic memory" says Khajetoorians. "This has a much bigger energy barrier and might be viable to make the single atom memory stable at room temperature."

"When we first conducted the experiment and saw this binary switching, we weren't sure what was going on," recalls Khajetoorians. "In a beautiful collaboration with theorists from Radboud University, Misha Katsnelson and Sasha Rudenko, we were able to point out that we were observing the atom's orbital moment and had created a new memory [medium]." It's still a magnet with spinning electrons, but now with an observable binary switch: Its orbitals.

(Haali/Shutterstock/Big Think)

Look closer

It's also worth noting that part of what allowed the Radboud team to get a clear view of what could be done was their decision to use Cobalt atoms against a substrate of semiconducting black phosphorus: A scanning tunneling microscope allowed them to "see" individual Cobalt atoms against the phosphorus background to gauge the binary behavior in their orbitals.

Next steps

There's no hardware yet that can take advantage of the researchers' findings. Still, it's exciting. As Khajetoorians concludes, "What this work means is that, if we could construct a real hard drive from all these atoms — and we are still a long way from that — you could store thousands of times more information."

10 pieces of wisdom from Alan Watts

With his collected letters recently being published, it's time to revisit this extraordinary thinker.

Wikimedia
Personal Growth
  • Though the British philosopher died in 1973, his work continues to make an impact.
  • A recently published collection, The Collected Letters Alan Watts, is a deep dive into his personal correspondences.
  • Watts was an early proponent for spreading Eastern philosophy to Western culture.
Keep reading Show less
Photo: Shutterstock / Big Think
Personal Growth
    • A recent study from the Department of Health and Human Services found that 80 percent of Americans don't exercise enough.
    • Small breaks from work add up, causing experts to recommend short doses of movement rather than waiting to do longer workouts.
    • Rethinking what exercise is can help you frame how you move throughout your day.
    Keep reading Show less

    Watch: The first AI-scripted commercial is here, and it’s surprisingly good

    A new AI-produced commercial from Lexus shows how AI might be particularly suited for the advertising industry.

    Lexus
    Technology & Innovation
    • The commercial was written by IBM's Watson. It was acted and directed by humans.
    • Lexus says humans played a minimal part in influencing Watson, in terms of the writing.
    • Advertising, with its clearly defined goals and troves of data, seems like one creative field in which AI would prove particularly useful.
    Keep reading Show less

    4 reasons why Apple, Facebook and other tech stocks are plunging

    The so-called FAANG companies have lost more than $700 billion in market value since October.

    (Photo credit should read BERTRAND GUAY/AFP/Getty Images)
    Politics & Current Affairs
    • The shares of major tech companies were performing exceptionally well earlier this year, but those gains got nearly erased on Monday.
    • Overvaluation, the U.S.-China trade war and recent privacy concerns surrounding tech companies are among the reasons for the drops.
    • Apple and Facebook have been hit the hardest in recent weeks, thanks in part to a few major reports from news outlets.
    Keep reading Show less