Slashdot Mirror
Individual Atom Memory Created
azav writes "University of Wisconsin-Madison Scientists have created "atomic scale" memory using individual atoms of Silicon." A cool photo can be found on the site as well.
← Back to Stories (view on slashdot.org)
Single atom memory? How stable do they REALLY expect that to be?
Ha! What's the name of the technology? Alzheimer's Access Memory?
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
.. not to be too repetitive, but this was posted only a month ago..
0 8/0116255&mode=thread&tid=126
http://science.slashdot.org/article.pl?sid=02/08/
about moore's law?
And a brick wall?
Methinks there is no higher density than bit-per-atom.
hrm... bit per electron...
If voting were effective, it would be illegal by now.
"If you can read this, you're WAAAY too close!"
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
As a matter of fact, yes.
Not all atoms are the same size. Remember what you learned about atomic weights?
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
"Reading the memory consists of a simple, one-dimensional scan, because it is self-formatted into precise tracks. There is no need to search in two dimensions for the location of a bit. The signal is highly predictable since all atoms have the same shape and occur on well-defined lattice sites. That allows for a high level of filtering and error correction"
"Writing is more difficult. While atoms can be positioned controllably at liquid helium temperature, that is much harder to achieve that at room temperature"
You just have to start storing multiple states in one atom. The Quantum Computing people have been talking about that for years.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
In 1959, physics icon Richard Feynman predicted that all the words written in the history of the world could be contained in a cube of material one two-hundredths of an inch wide.
And then we'd need a new search engine just to find the damn thing.
Fortunately, the text would probably be stored in the innovative MS Word format, which guarantees that the physical size of the required storage capacity will remain constant over time, no matter what the information density of the storage medium.
"I have opinions of my own, strong opinions, but I don't always agree with them." -- George H. W. Bush
Bartender replies "Are you sure?"
Atom thinks for a second: "Yea I'm positive."
The above post is an editorial, the poster cannot and will not be held responsible for all or in part for it's contents
I had an incredibly insightfull and informative post to make, but I stored it on an atomic scale memory smaller than a spec of dust. Now I can't remember where I put it.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
I found a remarkable proof of Fermat's Last Theorem, but this 512 terabyte memory cube is too small to contain it.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Actually, they are all rougly the same size, regardless of atomic weight. This is one of the interesting things about quantum mechanics and atomic physics. *All* atoms are between 0.5 and 2.5 Angstroms (1e-10 m)with Cesium being the largest (bigger than Uranium) and Nitrogen? being the smallest. Silicon isn't very large, however. This is partially because the electrons are so far away from a VERY tiny nucleus (remember the football field/grain of salt analogy).
$ solvechess
Please prepare and format 10 Dyson Spheres and fill them with crystalline silicon.
Please insert Dyson Sphere 1 and press enter...
Working..........(10%)
Please insert Dyson Sphere 2 and press enter...
Working...(13%), inf remaining.
Fun, fun, fun. And now we'll put those into a RAID 6+6. How many would you need at least and how many could fail before you lose any data? For bonus points, give the smallest possible distance you could leave between the spheres to keep them separated using no more than the power output of a Sol-like star on each and calculate the mass of all spheres combined. If possible draw a small diagram of how the spheres had to be placed for maximum stability.
Fight hunger. Filet a politician and send him to a 3rd world country of your choice.
If those are silicon atoms in the photo then what are the grooves in between the rows of atoms?
I know the secrets of the video game champs
In addition to requireing extra circuitry for decoding, this would require extra time. If you're wondering why CPUs don't just use various (16/32/64/whatever) voltage levels internally, then you really need a refresher course.
Transistor -> voltage controlled current source. i.e. a transister (in most cpus, these are nmos/pmos pairs) will either be "conducting" or "not conducting" a current depending on voltage level at the gate. Although technically these conducting/non-conducting will have slightly different currents flowing though them, we cannot use these as various voltage levels for the next transister because we get into all sorts of matching problems, fan-in/out problems, and basically (for example) the number "26" would be represented by one voltage level here, a different one there, and another one based on what transisters or conducting, and how much. If you're wondering why we don't use resisters to solve some of these problems, you REALLY need to review - power dicipated = current * current * resistance = heat. 20B currents squared * 20B resistances = instant chip incineration.
As a side note (actually two side notes) I beleive in the 40s they were experimenting with computers which used 10 voltage levels because that was the natuaral thing to do, until someone suggested using binary/boolean value which until that time were just a mathmatical curiosity than a dicipline taken seriously. I don't have references on hand ot back this up, but I think i remember reading something to that effect. The other side note is that many modems (even today) use variable-level voltages ot communicate. This is because the speed limiting factor effecting modems is line quality and length. It takes a relativly long time to force the line to any particular voltage, and so the modem makes these voltages count by encoding multiple levels. Ex. 9600bps modem uses 12 phase angles, four of which have two voltage levels, alowing to transmit 16 bits in one cycle (Stallings, Data & Computer Communications, 6th, p145). This is also why some modems (ex 56k) will only connect at (ex) 24k if excessive line noise prevents reliable encoding on many voltage levels.
The second reason we don't use variable levels in memory storage is error control. 1/0 values are screwed up enough by line noise, magnetic fields, and what have you. Imageine how difficult a time a machine would have dtermining "is that atom 23456 picometers about the base or 23457?"
As photonics emerges as a network technology though, I'm wondering if there is something like a "photo-transister" that will block or allow passthrough of light if light is present at a gate of a certain wavelegth. I know extreamly little about photonics, but if this possible then maybe multiple bits can be transmitted via multiple wavelengths inside a light-based (as opposed to electricity based) processor. Anyonw working on something like this?
Anyway, I hope this helps!
KeggInKenny
"A dictatorship would be a heck of a lot easier, there's no question about it." -George W. Bush
Actually, they are all rougly the same size, regardless of atomic weight. This is one of the interesting things about quantum mechanics and atomic physics. *All* atoms are between 0.5 and 2.5 Angstroms (1e-10 m)with Cesium being the largest (bigger than Uranium) and Nitrogen? being the smallest. Silicon isn't very large, however.
Hydrogen's the smallest, according to my books, with a radius of something like 0.53 angstroms (been a while since I looked it up).
What confuses me is why the atomic radii don't go up as the square of the number of shells. The alkali metals will have a single electron in the outermost shell, with the nucleus shielded by the inner shells, and so having an apparent charge of one. This seems to give a system with size equivalent to the nth energy level of an electron in hydrogen, which goes up as the square of the shell number.
I and the friends I asked about this speculate that because the electrons in the sheilding shells are smeared out radially, the outermost shielding shell extends past the valence shell's nominal radius, and so the core is only partly shielded, but I haven't seen any description to date of how you work out what the radii actually end up being.
Any pointers/quick explanations?
There's a PDF of the real journal article available from Nanotechnology's site.
In the article they say that their atomic memory has an energy density of 250 terabits per square inch (compared to 100 gigabits per square inch for a hard drive). A CD-ROM has 14 square inches of recordable area. If one were to use this technique on a surface the size of a CD-ROM, that would give:
(14 square inches) * (250 terabits/square inch) / (8 bits/byte) = 437.5 terabytes
Incredibly huge, but I'm sure there's a number of people who would still be able to fill it up.
actually all atoms are roughly the same size, hydrogens nucleus has little pull on its electron so the shell is relatively far out from the nucleus, but a massive atom such as uranium has the shell, relatively, closer in, the charges in a stable atom may be equal, but the positive charge is all concentrated in the center and acts on the electrons individually, brining them closer in, but of course if u wanna get weird, all atoms are theoretically infinite (heisenberg)
"Sic Semper Tyrannosaurus Rex."
For those who missed it, their 778 gigabyte database of the complete Awari game tree could be stored on a piece of silicon approximately 4mm square. Wait, that's just on one side! Sweet, we'll keep MP3s on the other 778 gig side.
(0.778 terabytes) / ((250 terabits/sq.inch) / (8 bits/byte)) = 0.024896 sq.inch =~ 4mm square
Cos atoms have a habit of moving about.
Deleted