Single Molecule Transistor A Reality

Petersko writes "A team from the University of Alberta has proven for the first time that a single molecule can switch electrical currents off and on, a puzzle that scientists worldwide have been trying to crack for decades. The finding could revolutionize the field of electronics, providing a leap ahead for everything from computers to batteries to medical equipment."

Comments

Other sources

[waynegoode]

Also read about it at the University of Alberta website and in the Press release

Re:Other sources

[Husgaard]

Or have a look at the home page of the researcher.

Re:How long until it's usable?

[rbarreira]

From TFA:

While a computer using this new technology is at least a decade away

...

The article in Nature

[waynegoode]

Also see the article in Nature.

Really slow device

[Husgaard]

The researcher admits to that: "It takes us on the order of minutes to change conditions that make current go or not, so for any computer technology, this thing is today impractical."

Still I think this is very interesting news. This is very early research. The speed will probably be improved, and the smaller dimensions of single-molecyle transistors can give space for more hardware to compensate for the speed.

If you don't know...

[Ghoser777]

I believe that's the molecular structure for caffeine.

Cool, but NOT Revolutionary

[ghutchis]

I work in the field of molecular electronics -- I'm sorry, but this doesn't sounds "revolutionary."

It's hard to comment before I've read the article, but there are a lot of other, very reliable single-molecule transistor experiments. In 2002, Nature called it a "discovery of the year." (Sorry, can't find the URL right now.)

There have been pretty good single-molecule transistor measurements in other groups since then.

Granted, if they're able to image the single molecular wire, that's a solid advance over other techniques. But it's hardly the solution to a 20-year old puzzle.

(By the way, it's more like 30 years since it was shown how a molecule could function as a switch. The first paper on the subject was published in 1973.)

-Geoff

Rainbows and Unicorns

[ghutchis]

"Made out of molecules"? What do you think they're made out of now? Rainbows and unicorns?

Chips aren't made out of molecules. Current semiconductors are made out of various forms of silicon crystal.

That's a lattice -- there aren't individual "silicon molecules" anywhere in there.

Just FYI.

yep, single-molecule transistors made previously

[jedibo29]

I work on sort-of-related stuff in condensed matter physics, and I have skimmed through some papers about the subject, and I had the same thought as the parent (though I was too lazy to post) - that it's cool, but not quite "revolutionary" and that other groups have come up with single-molecule transistors before.

Here's a link describing what two groups published in Nature back in 2002 about single molecule transistors (maybe what the parent post was referring to):

http://www.sciencedaily.com/releases/2002/06/02061 3073522.htm/

I briefly scanned through the Nature "News and Views" that introduces and supplies background for this recent paper (from today's Nature) and it looks like the main innovation is that the group used a different technique from earlier molecule transistors. According to that Nature article, previous groups relied on metalmoleculemetal types of molecular junctions. Apparently, these junctions have extra geometric complexity due to the metal-molecule coordination that can complicate the charge transport measurements. This group avoided the "geometric uncertainty" by using a junction on a semiconductor (silicon) instead of a metal. They apparently added a carbon atom with an unpaired electron as a 'dangling bond' on the surface of the silicon electrode to form the molecule-electrode interface. The interface is then a covalent bond, instead of the more complicated coordination bond from other molecular junctions. Anyway, that's why I gathered from a quick reading of the Nature summary article, but I don't know about the subject in much depth.

There's definitely a lot of potential with this stuff, though.

Re:I WONDER

[mol_transistor]

interesting discussion. our paper actually goes well beyond the HP work mentioned above. in fact, if you read further on the HP work, you will see that they eventually discovered, as many suspoected, that they had no (active) molecules in their device. the rotoxane, while a brilliant achievement of chemical synthesis, played no role in the observed current voltage spectra. so detailed characterization is very important. in the work we published today, for the first time it is possible to say definitively that one molecule is characterised - not more or less than one. we know where every atom is and we know the congifuration of the molecule. the other key to this work is that we have managed to make two electrodes serve as three. that is a crucial step as there isn't room to have three fine probes converge on a volume the size of a molecule lke styrene. the key is in the ability to charge one single silicon surface atom, with one single electron, near the one single molecule. the result is like a conventional field effect transistor. it is a robust effect that works at room T - unlike say the break junction work at cornell. i hope that helps answer some of the questions.

Re:How long until it's usable?

[Nogami_Saeko]

Or in this case, by RTFA, you find out that "Wolkow and the University of Alberta have filed for a U.S. patent on the technology.".

So universities that actually don't want to screw-over their researchers, and want researchers to actually hang around, rather than leaving to keep their intellectual property will do a joint-patent of some sort.

N.