IBM Shrinks Bit Size To 12 Atoms 135
Lucas123 writes "IBM researchers say they've been able to shrink the number of iron atoms it takes to store a bit of data from about one million to 12, which could pave the way for storage devices with capacities that are orders of magnitude greater than today's devices. Andreas Heinrich, who led the IBM Research team on the project for five years, said the team used the tip of a scanning tunneling microscope and unconventional antiferromagnetism to change the bits from zeros to ones. By combining 96 of the atoms, the researchers were able to create bytes — spelling out the word THINK. That solved a theoretical problem of how few atoms it could take to store a bit; now comes the engineering challenge: how to make a mass storage device perform the same feat as scanning tunneling microscope."
I think 12 atoms should be enough for everyone ... (Score:4, Informative)
. . . now as to shrinking that scanning tunneling microscope . . . that might take a while . . .
Is anyone aware of how "big" they are . . . I'm not thinking that the word "small" is appropriate . . .
Re:I think 12 atoms should be enough for everyone (Score:4, Informative)
To be fair, have you seen how big the first Magnetic HDD's were? Granted, different technology and they still stored a hell of a lot more than 5 bytes, but miniaturisation is only a matter of time.
Re:And... (Score:5, Informative)
There are theoretical limits to how much information can be stored in a molecule -- this given by the molar entropy, typically expressed in J/(K*mol). But it can also be expressed, more intuitively, as bits per molecule.
(Yes [wikipedia.org], you can convert between J/K and bits -- they measure the same thing, degrees of freedom.)
Per this table [update.uu.se], iron has a molar entropy of 27.3 J/K*mol, or 4.73 bits/molecule.
IBM is claiming an information density of (1/12) bits/molecule, which is reasonable -- the thermodynamic limit is ~57x greater.
Re:And... (Score:5, Informative)
So there is even more headroom in the thermodynamic limit.
Re:I think 12 atoms should be enough for everyone (Score:5, Informative)
An actual STM instrument is pretty big. About the size of, say, a mini-fridge. But the majority of that is the computer to drive the system, the readout electronics, and the enclosure (to dampen out vibrations, establish vacuum, etc.). The actual readout tip is pretty small: a nano-sized tip attached to ~100 micron 'diving board' assembly.
A related problem with STM is that it's a serial process: you have a small tip that you're scanning over a surface. This makes readout slow. However in a separate project, IBM (and others) has been working on how to solve that: the idea is to use a huge array of tips that scan the surface in parallel (IBM calls it millipede memory [ibm.com]). This makes access faster since you can basically stripe the data and read/write in parallel, and it makes random seeks faster since you don't have to move the tip array as far to get to the data you want. It increases complexity, of course, but modern nano-lithography is certainly up to the task of creating arrays of hundreds of thousands of micron-sized tips with associated electronics.
Using tip arrays would make the read/write parts more compact (as compared to having separate parallel STMs, I mean). The enclosure and driving electronics could certainly be miniaturized if there were economic incentive to do so. There's no physical barrier preventing these kinds of machines from being substantially micronized. As others have pointed out, the first magnetic disk read/write systems were rather bulk, and now hard drives can fit in your pocket. It's possible the same thing could happen here. Having said that, current data storage techniques have a huge head-start, so for something like this to catch up to the point where consumers will want to buy it may take some time.
Re:Bad article (Score:5, Informative)
The actual paper was published today in Science:
Sebastian Loth[1,2], Susanne Baumann[1,3], Christopher P. Lutz[1], D. M. Eigler[1], Andreas J. Heinrich[1] (Affiliations: [1] IBM Almaden Research Division, [2] Max Planck Institute, [3] University of Basel) Bistability in Atomic-Scale Antiferromagnets [sciencemag.org] Science 13 January 2012: Vol. 335 no. 6065 pp. 196-199 DOI: 10.1126/science.1214131 [doi.org].
The abstract is:
Some big names are on this paper (Don Eigler [ibm.com] is a pioneer of STM; responsible for the famous "IBM written with xenon atoms [ibm.com]" proof-of-concept, and along with Lutz worked on the also-famous "quantum corrals [wikipedia.org]").
Re:Vibration will be the biggest challenge (Score:4, Informative)
It's also worth noting that modern hard disks already position the read head staggeringly close to the platter already - on the order of 10nm of clearance or less. And this is in a consumer electronic device.
Most of the constraints of STM and AFM are related to the fact that they are general purpose, highly accurate devices, intended to study arbitrary samples (and work down to the 0.1 nm type scales while doing it).
Re:12 atoms? Go smaller! (Score:5, Informative)
There was a wonderful paper in Nature titled "The Ultimate physical limits to computation" by Seth Seth Lloyd (Yes the guy with the funny laugh), which discussed exactly how small computation and processing can ever get (Short of discovering new physics of course)
Entry page: http://arxiv.org/abs/quant-ph/9908043 [arxiv.org]
Direct PDF Link: http://arxiv.org/PS_cache/quant-ph/pdf/9908/9908043v3.pdf [arxiv.org]
It's a fascinating read, which I highly recommend. I believe it will answer your questions as well.
The summary of the paper:
Computers are physical systems: what they can and cannot do is dictated by the laws of physics. In particular, the speed with which a physical device can process information is limited by its energy and the amount of information that it can process is limited by the number of degrees of freedom it possesses. This paper explores the physical limits of computation as determined by the speed of light $c$, the quantum scale $\hbar$ and the gravitational constant $G$. As an example, quantitative bounds are put to the computational power of an `ultimate laptop' with a mass of one kilogram confined to a volume of one liter.
Re:The REAL question is... (Score:4, Informative)
You can make one now if you like. There's an article here [popsci.com] about someone working on an open source kit, but it also mentions other places that will sell you a kit to build your own.