Scientists discover new mechanism for information storage in one atom

Scientists at Radboud University discovered a new mechanism for magnetic storage of information in the smallest unit of matter: a single atom.

Adsorption and switching of Co on BP. a Six Co species on BP as deposited at T < 5 K (Vs = −400 mV, It = 20 pA, scale bar = 1 nm). Boxed atoms show species related through mirror plane along [010]. b Four atoms from a have been switched into JH,low (Vs = −400 mV, It = 20 pA, scale bar = 1 nm). c Two atoms from b have been switched into JH,high (Vs = −400 mV, It = 20 pA, scale bar = 1 nm). d Switching characteristics from JH,low to JH,high with Vs = 420 mV and e JH,high to JH,low with Vs = −680 mV. Approximate threshold biases for switching (Vth) are noted. Orange circles indicate the tip position during the switching sequence. The inset images showing before and after configurations are 4 nm × 4 nm in size. f Schematic representation of adsorption energy curves for Co species on BP.

Scientists at Radboud University discovered a new mechanism for magnetic storage of information in the smallest unit of matter: a single atom. While the proof of principle was manifested at very low temperatures (room temperature). In this way, it will be possible to store a thousands of times more information than in current hard drives. 

As our current computing architecture is not getting much faster and using a lot of power, combined with the demands to store information. One potential pathway is to store information at the ultimate scaling limit: a single atom.

Brian Kiraly, first author explains, "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. 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. Now our only question is: How can we store information within a single atom and how stable can we make that piece of information?"

When you get down to the single atom level, atoms which are magnetic, no longer remain stable. "What defines a permanent magnet is that it has a north and a south pole, which remains in the same orientation," professor of Scanning Probe Microscopy Alexander Khajetoorians explains, "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."

"For the last ten years researchers have been asking: in order for the atom to stop flipping, how many atoms are needed to stabilize the magnet, and how long can it hold it information before it flips again? In the last two years, scientists in Lausanne and at IBM Almaden have figured out how to keep the atom from flipping, showing that a single atom can be a memory. To do this, researchers had to use very low temperatures, 40 Kelvin or -233 degrees Celsius. This technology is limited to extremely low temperature."

Scientists at Radboud University took a different approach. By choosing a special substrate – semiconducting black phosphorus - they discovered a new way to store information within single cobalt atoms, that bypasses the conventional problems with instability. Using a scanning tunneling microscope, where a sharp metal tip moves across their surface just a few atoms away, they could "see" single cobalt atoms on the surface of black phosphorus. Because of the extremely high resolution and the special properties of the material, they directly showed that the single cobalt atoms could be manipulated into one of two bit states.

The electrons in an atom orbit around the nucleus, but also "spins" themselves, much like the Earth rotates both around the Sun and its own axis. The total amount it spins, or its angular momentum, is what gives us magnetism. Instead of this spin angular momentum, which previous researchers have used, they 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. This has a much bigger energy barrier and might be viable to make the single atom memory stable at room temperature.
In the end, it is still a magnet with an angular momentum, but we are now able to control the atom from 0 to 1 state, which has a much higher stability than other magnets," says Kiraly.

Khajetoorians adds, "When we first conducted the experiment and saw this binary switching, we weren't sure what was going on. 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."
Right now, the elements that store hard drive bits are still a thousand times bigger than an atom. Khajetoorians says, "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."

This research are published today in Nature Communications.


Subscribe Newsletter


Scien-Tech News: Scientists discover new mechanism for information storage in one atom
Scientists discover new mechanism for information storage in one atom
Scientists at Radboud University discovered a new mechanism for magnetic storage of information in the smallest unit of matter: a single atom.
Scien-Tech News
Loaded All Posts Not found any posts VIEW ALL Readmore Reply Cancel reply Delete By Home PAGES POSTS View All RECOMMENDED FOR YOU LABEL ARCHIVE SEARCH ALL POSTS Not found any post match with your request Back Home Sunday Monday Tuesday Wednesday Thursday Friday Saturday Sun Mon Tue Wed Thu Fri Sat January February March April May June July August September October November December Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec just now 1 minute ago $$1$$ minutes ago 1 hour ago $$1$$ hours ago Yesterday $$1$$ days ago $$1$$ weeks ago more than 5 weeks ago Followers Follow THIS PREMIUM CONTENT IS LOCKED STEP 1: Share. STEP 2: Click the link you shared to unlock Copy All Code Select All Code All codes were copied to your clipboard Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy