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Cascading Molecules Drive IBM's Smallest Computer
Benoit Fries writes "EE Times reports that IBM researchers have created a simple computation engine that's more than 250,000 times smaller than the most advanced silicon circuitry. Called the world's smallest computer, the system relies on a 'molecular cascade' that pushes a handful of carbon monoxide molecules across a copper surface to perform digital logic functions. 'Even if CMOS density follows Moore's Law for 40 more years, molecular cascades are still going to be smaller,' they said."
All those people worrying about asphyxiating on carbon monoxide...
CO binds very tightly to metallic ligands such as copper. The Carbon atom has an unbound lone pair of electrons, that are donated to the metal's d-electron shell. Additionally the CO molecule creates a pi-back-bonding system with the metal center, making the complex even more stable.
Upshot: the CO is not going to spontaneously leak off the chip into your atmosphere. In any case, I doubt that such logic circuits would contain sufficient carbon monoxide to pose a health threat.
(Interesting side note: CO asphyxiates you by binding very tightly to the iron in hemoglobin in your blood, much more tightly than oxygen can. IIRC, however, CO will preferentially bind to copper over Fe.)
My other sig is also a
Aw, I was almost getting excited as I read the article. This technology appears to be a long way from being a post-silicon circuit alternative for CPUs.
:)
It's "exceedingly slow," according to the article. Still, maybe some kind of niche exists for it to be useful. Then again, maybe they'll implement the NOT gate and get this puppy running near the frequency of 500nm light or something.
I'd be excited by that.
You can read the express paper at Science.
My first thought was, the structure once toppled, IS toppled, and with a stationary background, it would not be possible to reset it. I found it is indeed true. In the IBM page, it states
...It takes several hours to set up the most complicated cascades. Since there is no reset mechanism, these molecule cascades can only perform a calculation once....
My idea is, have a non-stationary background of copper plane, which through some mechanism (which causes repulsion of the CO molecules) places the molecules in the reset position, ready to be "toppled" again!
"Do something man. Right now."
You have to learn entirely different programming methods to program algorithms to run in parallel. Managing memory and cache access between multiple processors is a pain in the ass on the hardware side. That's what makes mobos for multiple processors more expensive. Plus, some tasks are just not well-suited to scaling across multiple processors at all.
In short, I'd rather have a one processor machine over a two or more processor machine if the one processor machine gives sufficient speed for a reasonable price.
Maybe the state's highest function is to grind out insoluble problems. (Zelazny, Hall of Mirrors)
If a cascading molecule NOT gate is hard then thier cascading domino metaphor must not be accurate... It's easy to build a domino NOT gate. Here's how:
:
TtttttttttttttR
i
i
I
It's 2 runs in an L shape. Simultaneously gate a True signal at T and the input signal at I, read the result at R. Note: True = Falls, False = Stands.
Here's how it works
If I = True then the shorter I run knocks down the last t. When the longer T run reaches R, the last t will already have fallen so R will not fall. so we have:
I = True --> R = False
If I = False then the T run will knock down R. So we have:
I = False --> R = True
That's a NOT gate!
Combine that with a V shaped OR gate and you have a NOR gate. It's well known that any logic function can be constructed from NOR gates.
Jonathan Weesner
Hard drive manufacture is already carcinogenic, as it involves multiple washes with solvents with known carcinogenic activity (e.g. xylene). WiReD had a story about this several issues ago (late last year? if you search their website i'm sure you'd find it in the archives; specifically mentioned was IBM's HD plants which had cancer incidences several sigma higher than normal in their workforce).
Well...
:) :
:)
Applying a little physics (but not too much, since I don't have the references or the desire/ability to go through the really rough calculations
The "average" air molecule travels at about 300 meters/sec at room temperature. This speed is a multiple of the temperature T, divided by the mass m of the molecule - E=3/2kT=1/2 mv^2 (so CO is a little faster than average, since Carbon is lighter than Oxygen or Nitrogen)
So, if they can build room temperature versions of this (the sample was at 4-10 K), and the size remains about the same (17nm across), and the molecules travel say half their speed in atmosphere, and the computational nodes get "recharged" as fast as they calculate, then the thing would be able to go at about 4.4 GHz.
Not too bad, actually.
Probably within an order of magnitude, at least (ie, wrong
- The Sigless Wonder
Read this:-
Unbounding the Future: the Nanotechnology Revolution
Eric Drexler and Chris Peterson, with Gayle Pergamit William Morrow and Company, Inc.
I don't know where I downloaded it from, but it's a free ebook (.DOC format) download.
I can send you it in PDF if you're interested enough and contact me.
Conversion Rate Optimisation French / English consultant