Tiny 'Atomic Memory' Device Could Store All Books Ever Written

A new "atomic memory" device that encodes data atom by atom can store hundreds of times more data than current hard disks can, a new study finds.

"You would need just the area of a postage stamp to write out all books ever written," said study senior author Sander Otte, a physicist at the Delft University of Technology's Kavli Institute of Nanoscience in the Netherlands.

In fact, the researchers estimated that if they created a cube 100 microns wide — about the same diameter as the average human hair — made of sheets of atomic memory separated from one another by 5 nanometers, or billionths of a meter, the cube could easily store the contents of the entire U.S. Library of Congress. [10 Technologies That Will Transform Your Life]

"Of course, these estimations are all a little silly, but in my opinion, they help to get an idea of how incredibly small this memory device really is," Otte told Live Science.

Information overload

As the world generates more data, researchers are seeking ways to store all of that information in as little space as possible. The new atomic memory devices that researchers developed can store more than 500 trillion bits of data per square inch (6.45 square centimeters) — about 500 times more data than the best commercial hard disk currently available, according to the scientists who created the new devices.

The scientists created their atomic memory device using a scanning tunneling microscope, which uses an extremely sharp needle to scan over surfaces just as a blind person would run his or her fingers over a page of braille to read it. Scanning tunneling microscope probes can not only detect atoms, but also nudge them around.

Computers represent data as 1s and 0s — binary digits known as bits that they express by flicking tiny, switch-like transistors either on or off. The new atomic memory device represents each bit as two possible locations on a copper surface; a chlorine atom can slide back and forth between these two positions, the researchers explained.

"If the chlorine atom is in the top position, there is a hole beneath it — we call this a 1," Otte said in a statement. "If the hole is in the top position and the chlorine atom is therefore on the bottom, then the bit is a 0." (Each square hole is about 25 picometers, or trillionths of a meter, deep.)

The bits are separated from one another by rows of other chlorine atoms. These rows could keep the bits in place for more than 40 hours, the scientists found. This system of packing atoms together is far more stable and reliable than atomic memory strategies that employ loose atoms, the researchers said. [How Big Is the Internet, Really?]

These atoms were organized into 127 blocks of 64 bits. Each block was labeled with a marker of holes. These markers are similar to the QR codes now often used in ads and tickets. These markers can label the precise location of each block on the copper surface.

A scan of the 1 kB memory, written to a section of "On the Origin of Species" by Charles Darwin.
Credit: Image courtesy of TU Delft
The markers can also label a block as damaged; perhaps this damage was caused by some contaminant or flaw in the copper surface — about 12 percent of blocks are not suitable for data storage because of such problems, according to the researchers. All in all, this orderly system of markers could help atomic memory scale up to very large sizes, even if the copper surface the data is encoded on is not entirely perfect, they said.

A big step

All in all, the scientists noted that this proof-of-principle device significantly outperforms current state-of-the-art hard drives in terms of storage capacity.

As impressive as creating atomic memory devices is, Otte said that for him, "The most important implication is not at all the data storage itself."

Instead, for Otte, atomic memory simply demonstrates how well scientists can now engineer devices on the level of atoms. "I cannot, at this point, foresee where this will lead.

Credit:livescience