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Silicon Superconductors
Diana writes "Physicists at CNRS have demonstrated superconductivity in silicon, the element long known for its semiconducting properties. High doping is the key — by substituting 9% of the silicon atoms with boron atoms, it was found that the resistance of the material drops sharply when cooled below 0.35 K. A small increase in the transition temperature is likely with further work."
"A small increase in the transition temperature is likely with further work."
It could go as high as 0.40K. Hooray.
Pretty much anything will superconduct below 0.35K. How is this news?
Who the fuck cares about some superconductor that will only work below 0.35 kelvin? The expense of any machinery capable of cooling something to 0.35 kelvin far outweighs the neatness of being able to do it with silicone too.
But you can make pretty much anything superconductive if you get it down below .5 Kelvin. I mean really, go much lower and you can make Twinkies superconductive much less boron doped silicon.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
Superconductivity in non-superconductive materials, except where they've been doped to be superconductive.
Makes me want to get back to the pub.
668: Neighbour of the Beast
What non-consumer applications will it have? Getting something down to
IIRC, anything that doesn't superconduct at the temp of liquid nitrogen is a pain in the ass to use.
[Fuck Beta]
o0t!
whatever that means!
How is that useful? Only Canada gets that cold!
What a coincide, 0.35 K is the same temp I keep my house ;)
And just to make the article more clear: Let's substitute "boron" with Tom (hey, what guy wouldn't want more boron?), and "silicon" with Suzie (hey, what girl woudln't want more, eh, yeah.).
"Because it has one fewer electron than Suzie available for bonding with neighbouring atoms, Tom incorporated into Suzie leaves a positively-charged "hole" at each site where Tom's "missing" electron would be paired with one of Suzie's."
Well they did do it in France, you know.
If we can turn semiconductors into superconductors, then we can probably turn my band conductor into a semi-conductor, which would at the very least mean less thrown chairs during parent teacher conferences, and less thrown chairs can only be good for Linux!
(Yes, that happened; and yes, he is still in band director.)
When things get complex, multiply by the complex conjugate.
Since when did science have to have applications?
(This isn't sarcasm; science is about discovery. Applications of those discoveries are mostly accident. You can't automatically "succeed" at science. Failing to find a room-temperature superconductor isn't failing per se; it means succeeding to eliminate another coulda been material. Finding dead ends is part of the quest. And this result might not yet be a dead end.)
So far, most of the comments have been posted by boring morons.
-A bored moron
At 0.35K it will only ever work in Canada. So Winterpeg could become a mecca of supercooled computing yet...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Boron was made superconducting by doping it with 90% silicon.
I work on a radiotelescope that uses receivers cooled to 4K. These use a helium refrigerator that works just like the Freon thing in your car but using helium instead of Freon as the phase-change medium. It takes three stages of cooling (with compressors and heat exchangers) to get to the 4K point. It also takes 10 kW of electrical power to cool one watt of load to 4K.
We until recently had one receiver, a bolometer, that was cooled to 0.4K using the 3He isotope of helium that has a lower boiling point. The refrigerator for this is a fist-sized gadget that uses a charcoal trap, a heater resistor and some plumbing to make a refrigerator that can be cycled to produce 0.4K for a day or so at a time. It makes many microwatts of 0.4K coldness from less than one watt of 4K coldness.
Unfortunately, the 3He leaked out and the gizmo is currently a paperweight since it was made by a very clever French guy who's no longer in the business.
You can still buy 3He refrigerators from other manufacturers, but they are two feet long. The 3He is available for several thousand dollars a bottle.
The determined Real Programmer can write Fortran programs in any language.
Yes, 0.35 K is really cold. Refridgeration methods that reach this temperature cost ~ $100,000 and use the helium-3 isotope as the working fluid, which costs several hundred dollars per gaseous liter at STP. But this may still be useful because there is lots of established technology for making very small things out of silicon, and lots of fundemental physics that can only be done at very small length scales and in very cold environments.
This goes to show that even silicon when doped get high!
--
Now, that's a sig!
Help a man when he is in trouble and he will remember you when he is in trouble again.
I tried super-doping myself but it got boron after a while.
spoonerize "magic trackpad"
...but I like you...
668: Neighbour of the Beast
High doping is the key to everything, man..
Yes, I understand the need for and value of pure science. Yes, I understand that new discoveries may take years or decades to have a commercial use.
So?
That doesn't make this news. The ability to make things superconduct at vanishingly low temperatures is nothing new.
Now, when this leads us to an understanding of the why and how behind superconductivity, _that_ will be news. When this leads us to something that superconducts at a temperature reachable by your average refrigeration system, _that_ will be news. Until then, this is simply business as usual in the world of research.
A small increase in transition temperature was the last thing we needed at this point. What little luck we had left was spent during the gravitational slingshot and none of us needed a glance at the holo-panel to know the ion shields had only minutes before a collapsed inner hull went from worry to worse.
Without saying it aloud, we all knew the survival of the ship...our survival...was totally dependent on staying out of sensor range for just a bit longer. The sub-orbital alerting buoys, with their grid-multiplied scan vectors and frequency-hopping proximity background energy detectors, had only to exert minimal effort before group consensus deemed us an unauthorized guest.
Please! Since when everything is supposed to make sense only if it has tech applications? You seem to be missing the point of science really. The fact that doped silicon exhibit superconductivity is per se a great discovery. There are plenty of examples of "useless" science: black holes, dark matter, superfluidity. You may not care (busy playing your new PS3?). The rest of us really do.
substituting 9% of the silicon atoms with boron atoms, ...That means doping boron, not silicon.
I've been watching too much of the original Battlestar Galactica. With their "centons", "sectons", "furlons", "crawlons", and of course "Cylons", when I saw the term boron, my first thought was that it was some sort of unit of boredom. Then I read the article, and realized I was right.
When our name is on the back of your car, we're behind you all the way!
So I guess Pamela Anderson is more useful than we thought! Other than the obvious, of course. ;-)
This character reminds me of him.
I can do things I normally can't when I'm doped, too.
Property is theft.
Silicon dopes you.
Life would be easier if I had the source code.
Damn, I guess this water cooling system isn't going to cut it for my next upgrade.
Refridgeration methods that reach this temperature cost ~ $100,000 and use the helium-3 isotope as the working fluid, which costs several hundred dollars per gaseous liter at STP.
You can get a He3 system (which will get you down to ~0.25-0.3K with very little work) for just under $50k, and since it's a closed system you don't have to buy any more helium-3.
As a low temperature physicist, I have a hard time thinking of 0.35 K as unbeliveably cold. That's the temperature I get when my dilution refrigerator has a heat leak (and my fridge is not very good). Good dilfridges can get down to 0.015K or so, but they require more TLC than a He3 system.
Some years ago, evidence for superconductivity was found in a gallium arsenide epitaxial device. The work was duly published, and only some time later was it realised that the superconductivity was occurring in metallic indium on the back of the device - the indium had been used as a good thermal conductor for mounting the GaAs substrate in the epitaxial growth chamber, and had not been completely removed.
If these guys have done their work carefully, they will have gone to great lengths to ensure that they really are measuring doped silicon, and not boron-rich precipitates, which might be formed at these very high boron doses.
We've been able to create chips with Niobium implanted in silicon for quite a while, and Niobium superconducts at similar temperatures
This sig wasn't worth reading, was it.
Will this make my dial up connection faster?
I'm in to sadism, bestiality and necrophilia. Am I flogging a dead horse?