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IBM Creates Ring Oscillator on a Single Nanotube
deeptrace writes "IBM has combined CMOS circuitry and a single carbon nanotube to implement a 5 stage ring oscillator. Even though the oscillator runs at just 52 MHz, they expect that it could reach the GHz range with improvements. The frequency of the current oscillator was higher than previous circuits using multiple nanotubes. IBM describes the achievement in the paper "Integrated Logic Circuit Assembled on a Single Carbon Nanotube" to be published this week in the journal Science."
Religion for nerds. Stuff that really matters
Some of us are not nano-physicists/EEs, so it's not clear as to what the big deal is.
Now let's talk about REAL innovation. Microsoft just announced a new facial feature pack for Office's "Clippy." Now you can customize Clippy according to your facial preferences. Options include complexion, hair style, nose shape and size, and ear/nose jewelry.
I had some imprevements for breakfast; they were a bit stale, so they tasted xor.
What exactly this means?
hilarious
Right in the middle of the 6-meter Amateur Radio band! Sounds like a nice local oscillator for an ultra-tiny nano "rig". Now, to figure out how to directly modulate it for direct FM or FSK.
-- You are in a maze of little, twisty passages, all different... --
Microsoft announced today that they have achieved a full annoyance oscillator and generator on a single virtual piece of bent metal.
The findings titled "How to make Clippy more annoying" will be published next week in the Mr. Ballmer's Journal of IBM Bashing
a ring Oscillator!
On a Single Nanotube!
crap all mighty!!!
They're just showing off.
It's nothing but a token ring.
=brian
...at the IBM labs Oh yeah! Nanotech really turns the hot chicks on
FYI - a ring oscillator is just a proof of concept and there is no practical application, per se. It shows that their carbon nanotube transistor technology is well understood enough so that they can make simple logic devices (an oscillator is a bunch of inverters (NOT gate) strung together. Not long ago, slashdot had an article about a transparent ring oscillator from Oregon State Univ. Again, this was done as a stepping stone from discovering an entirely new semiconductor (this is NOT silicon, people) to making a useful device.
A carbon nanotube (CNT) is a rolled graphene plane (ie, carbon atoms in a hexagonal structure). So of course all current will be on the 'outside' of the tube, as the tube itself really only consists of the outside.
IBM was probaby comparing single-wall nanotubes to multi-wall nanotubes. Multiwall nanotubes are composites of a bunch of concentric single-wall nanotubes. Their better results in the single-wall variety are probably due to less scattering between the graphene planes. A single CNT has a well-defined crystal structure, and is actually quite interesting. The graphene plane itself is sometimes referred to as a 'zero-bandgap insulator', where the density of states linearly goes to zero at the fermi energy (unlike an insulator or semiconductor which has a energy gap at the fermi energy, and hence cannot conduct decently like a metal).
However through changes to the nanotube material, the performance of the nanotube may be impreved.
They probably can get to higher frequencies. I mean, even the vibrational phonon modes of a single nanotube can be in the GHz range or higher (ie, these are the various modes of vibration that the nanotube would exhibit if you struck it, kind of like a wind chime). I don't know specifics, but I don't see why the nanotube couldn't support electronic channels with bandwidths into the GHz or even higher as well.
Although nanotubes do have interesting characteristics different from typical metals and semiconductors. Ie, the electron-phonon interaction goes as 1/T, instead of 1/T^5 (where T is temperature). So at low temperatures there might be useful ways to couple electronic channels to vibrational modes not possible in conventional materials. Or vice versa, the phonon modes might more easily kill off electronic signals. There's alot of interesting work being done with nanotubes, and I'm sure some clever physicists and engineers will exploit these characteristics well in the near future.
Which is why communism fails. If everyone's the same regardless, there's no incentive to innovate. But that's aside the point.
Patents aren't evil, in fact there's nothing wrong with them. It's copyrights that are abused. A patent is to protect your work. A copyright is to extort as much money as possible from something that serves absolutely no tangible purpose. But rest assured, it will be patented. My dad co-holds a patent that's used in the process of wafer processing, and it's in fact an extremely simple concept (of course, considering the fact that by age twelve I came up with a solution that increased the accuracy of their heating uniformity data, which was another extremely simple concept, I'd really have to wonder how smart most of the engineers are). Other manufacturers, to my understanding, can pay to license the idea and use the technology- it's not being reserved exclusively for the patent-holder.
How are sites slashdotted when nobody reads TFAs?
That's the same circuit mentioned in the recent transparent IC story where TFA said
A 5-stage ring oscillator is the hardware equivalent of a program that displays 'Hello World!'
Does anyone else get the impression that most people have no idea the potential for nanotech? Or maybe those that do are just schizo and nerdy.
OK here's the explanation in 1337:
Carbon nanotubes = t3h w00t
CMOS = reality
Ring oscillator = first tests to integrate t3h w00t into reality
It means that before this, nanotubes and nanotube transistors were only tested in the lab, using microscopic clamps, cables, probes, etc. But this is the first time that a carbon nanotube can be integrated into a working CMOS chip (a small step for chips, a giant leap for mankind). Once CMOS manufacturing can be adjusted for carbon nanotubes, we'll be able to manufacture nanotube memory, nanotube chipsets, and finally, nanotube CPU's!
This is what i've been waiting for since i ever heard about nanotube transistors (however, i think that using graphene sheets instead of nanotubes will be much more effective).
Lets see if this helps. Some people were confused...
A ring oscillator is a device for making square waves. It uses a common component, a NOT gate. In digital logic, there are two levels, high and low (or 1 and 0, respectivly). High is usually, as far as I have seen, +5 volts, while low is 0 volts (ground).
A NOT gate simply inverts the input. If the value is 1, it outputs 0. If the value is 0, it outputs 1. If the value is somewhere between the two, it will choose one state or the other based on some threshold voltage.
Changing output is not instantaneous. How much time it takes, I don't know. However, it is very fast.
I was going to draw a schematic, but I gave up on appeasing the lameness filter. So, we will use the power of imagination! Imagine one of these NOT gates hooked up to itself. It will switch on and off at a terrific rate. Put a wire on the output, and you have a square wave! Want it slower? Take another two NOT gates, and put them in the loop, so that the first one goes to the second goes to the third. Slower? Another two. If the number of NOT gates was even, the inverted signal would be uninverted by the next NOT gate, which is not what we want.
For more control, one can use a capacitor in a certain arrangment (I'm not looking through my notes). It will take a while to charge and discharge, acting as a delay. Just don't read its voltage as the signal, or you will get a dropping bit, then a rising bit, rather than a nice clean square wave.
Quite useful devices. I hope this clarifies things.
I have freaks! I did something right...
If you're considerring using carbon nanotubes as a sex toy...you've got a problem. A very, very small problem, in fact.
GENERATION 26: The first time you see this, copy it into your sig on any forum and add 1 to the generation.
Some people seem to be wondering if this is just showing off, or are there short to medium term applications for this? I think that one of the first, fairly simple applications for this is in the field of gate arrays. FPGA's, or field-programmable gate arrays, are cool devices that emulate strings of logic gates. They can be used in circuit design tasks, emulating loads on networks, and any number of geeky things. FPGA's are often considered the ugly step sister to application-specific integrated circuits, or ASIC's. Why? Because they suck more power and they're slower. People still use FPGA's a lot of the time because they're more flexible, you can change them on the fly. Now imagine an FPGA that's ultra-miniaturized, drawing almost no power, producing very little heat, and operating at amazing speeds. They need to perfect NAND or NOR gates, but once they have one of those, they can replicate them a billion times, and either of those gate types will be able to emulate every other logic gate, when placed in the right order. That's one interesting application, on the pure logic level. So it might be an exciting time, depending on how quickly they can move this out of the lab. I love this stuff.
Bill Ricardi - Jigsale LLP
against ring osculation. It's disgusting and vulgar. What's wrong with just holding hands, or kissing on the lips? Miss O'Tube should be ashamed of herself. With a reputation like that, she's going to stay single. Back to you, Cheddar.
From the article: "Circuit designers understand that n-type transistors can be turned on with positive voltage applied to the drain; p-types are exactly the opposite."
Surely they mean 'applied to the gate' (the input voltage is gate to source, the output voltage is drain to source)
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All nanotubes are made up of this graphene plane.
Actually, you can make nanotubes out of other materials besides carbon. Metallic nanotubes, for example, will have different crystal structures than the graphene hexagon.
A tube with 100 atoms will have 100 distinct oscillating modes.
No, it will have 300, one for each degree of freedom. However, three of these will be translational modes, which are not phonon modes, so really there will be 297 distinct phonon branches. In addition you should distinguish between the number of atoms in a Carbon Nanotube, and the number of atoms in its unit cell. A unit cell may have 100 atoms, but the entire nanotube can be made of 1000s of unit cells. The number of atoms in the unit cell is the important number for calculating phonons.
I was going to make a smartass remark about being able to use "new and improved" trinary computers, with positive, negative, and neutral voltages on these transistors, but then I found out they already exist!
D'oh!
Well, at least I can welcome our ternary computing overlords!