Thinnest Silicon-chip Wires Refuse to go Quantum - Polidicks

[img]http://www.newscientist.com/img/misc/ns_logo.jpg[/img] [quote=NewScientist] [b]Thinnest silicon-chip wires refuse to go quantum[/b] Not everything is weird at the nanoscale. Wires so small you'd expect them to obey the strange laws of quantum mechanics have instead displayed the same electrical properties as ordinary electrical interconnects. The finding bodes well for conventional computers, because these tiny, conductive wires could make chips smaller. It could be bad news, though, for the super-fast quantum computers that are hoped to come next. So far, conventional computers have followed Moore's law: the density of transistors that a conventional integrated-circuit chip can hold doubles approximately every two years, yielding ever-better performance out of ever-smaller devices. However, it's getting harder to build smaller interconnects to wire up the devices on the silicon chip. As the width of metal wires drops to few tens of nanometres, their resistivity soars because electrons start interacting with nearby surfaces, dissipating more heat and lowering efficiency. [b]Phosphorous infusion[/b] Also, as wires get down to nanometre scales, quantum behaviour usually dominates. For instance, the entire wire can exist in a superposition of states because of a property called quantum coherence. The wave behaviour of electrons in the wire might then cause them to interfere with each other, disrupting the electrical properties you would expect to see at larger scales. Now, Michelle Simmons of the University of New South Wales in Sydney, Australia, and colleagues have etched channels in a silicon chip just 1.5 nanometres wide that behave just like larger wires. The trick was to infuse them with phosphorus atoms, which provide electrons that can move freely and conduct electricity, turning each channel into a wire. Because the entire wire, except for its ends, was enclosed in the silicon, it was isolated from other surfaces that could disrupt its conductivity. [b]Coolly classical[/b] The team found that these wires conducted electricity nearly as well as state-of-the-art copper interconnects used in modern microprocessors – despite being much thinner. Moreover, when they built wires of different lengths, the wires followed Ohm's law, in which the resistance of a wire increases with length – a property of non-quantum, or "classical" conductors. The lack of quantum behaviour surprises David Ferry of Arizona State University in Tempe – especially because the experiments were carried out at a mere 4.2 kelvin. "Usually when you go to [such] low temperatures, you expect quantum mechanics to dominate the world. Here they have Ohm's law, suggesting that it's just like classical behaviour at room temperature," he says. He reckons the large number of phosphorus atoms in the wire provided a very high density of electrons (1021 per cubic centimetre) and that their mutual scattering destroyed any quantum coherence, leading to classical behaviour. That bodes well for doing the experiment at higher temperatures. "If they behave classically at low temperature, then they are also likely to behave classically at room temperature," says Simmons. [b]Coherent problem?[/b] Indeed, Simmons says that the new wires are great news for those hoping for ever-tinier computing devices. "It shows that you can maintain low resistivity and make very thin conducting wires, which is obviously essential for down-scaling devices towards the atomic scale," she says. The implications for quantum computing are less clear. Simmons's team had already shown that individual phosphorus atoms can exist in a superposition of spin states, making up the quantum bits, or qubits, needed for quantum computation. She thinks that the nanowires could be used to interconnect qubits and help build quantum circuits. Ferry thinks otherwise. "This lack of quantum coherence is good for Moore's law, but it's bad for quantum computing, because you need quantum coherence for quantum computing. This may make it less likely to occur." [/quote] [url=http://www.newscientist.com/article/dn21333-thinnest-siliconchip-wires-refuse-to-go-quantum.html]Source[/url]

I learn more about science here than I do in school. [sub]It's more entertaining too[/sub]

Oh shit, this is the first scientific article here I've ever understood. Years of science classes have finally paid off

Woah, particle behaving like on the macro scale when you think it should be all screwy? That's like, doubly quantum.

maybe if they turn their backs

[quote]The implications for quantum computing are less clear. Simmons's team had already shown that individual phosphorus atoms can exist in a superposition of spin states, making up the quantum bits, or qubits, needed for quantum computation. [B]She thinks that the nanowires could be used to interconnect qubits and help build quantum circuits.[/B] Ferry thinks otherwise. "This lack of quantum coherence is good for Moore's law, but it's bad for quantum computing, because you need quantum coherence for quantum computing. This may make it less likely to occur."[/quote] thanks Ferry but I don't trust anyone with a webpage that looks like this [url]http://ferry.faculty.asu.edu/fun.htm[/url] [img]http://ferry.faculty.asu.edu/images/Ferry001smaller.jpg[/img]

you know, screw Moore's law, quantum computing is more important

[QUOTE=minilandstan;34125144]I learn more about science here than I do in school. [sub]It's more entertaining too[/sub][/QUOTE] School: Today we learn about enzymes... yeah... Internet: String theory, yeah! Temporal shifts, yeah! Quantum mechanics, yeah! Applied fluid dynamics, yeah! Space, science & Sagan!

[QUOTE=mac338;34125976]School: Today we learn about enzymes... yeah... Internet: String theory, yeah! Temporal shifts, yeah! Quantum mechanics, yeah! Applied fluid dynamics, yeah! Space, science & Sagan![/QUOTE] yeah enzymes how useless! biochemistry is [I]so[/I] last century

Point being you don't learn [I]new[/I] stuff at school only shit you know from before. EDIT: Though I really sucked at conveying that point.

[QUOTE=mac338;34126009]Point being you don't learn [I]new[/I] stuff at school only shit you know from before.[/QUOTE] Really, you know everything there is to know about enzymes? Or everything that they are teaching you? you should really inform your teacher so you can stop wasting everyone time and just start university already

[QUOTE=Contag;34125523]thanks Ferry but I don't trust anyone with a webpage that looks like this [url]http://ferry.faculty.asu.edu/fun.htm[/url] [img]http://ferry.faculty.asu.edu/images/Ferry001smaller.jpg[/img][/QUOTE] Dude, we all know the worse a website related to a scientist is, the better a scientist they are. It's like their desk- if it's clean, you know they've got too much time on their hands. If it's a clusterfuck of coffee-stained papers, random tools, half-eaten lunches and prophylatics, you know they [I]get shit done.[/I] [QUOTE=Contag;34126019]Really, you know everything there is to know about enzymes? Or everything that they are teaching you? you should really inform your teacher so you can stop wasting everyone time and just start university already[/QUOTE] To be fair, the only conditions where he'll need to remember or apply anything related to enzymes also involve taking proper bio classes in college.

Honestly, I'm sort of afraid of quantum computing. Not because I don't think it would be a good thing, but because I'm afraid they'd have to break the x86 trend to feasibly do it. I'm afraid that nothing we have now would work on quantum computers. Of course it's possible that I just don't understand quantum computing or the x86 instruction set as well as I thought I did, but there's always that possibility.

[QUOTE=Xenocidebot;34126101] To be fair, the only conditions where he'll need to remember or apply anything related to enzymes also involve taking proper bio classes in college.[/QUOTE] And the only conditions where he'll need to remember quantum physics or apply anything related to quantum physics on a proper technical level also involve taking proper physics classes in college. Of course he's more interested in what gets headlines.

[QUOTE=Dr.C;34125183]Oh shit, this is the first scientific article here I've ever understood. Years of science classes have finally paid off[/QUOTE] You guys have "Science" classes?

[QUOTE=Bat-shit;34126322]You guys have "Science" classes?[/QUOTE] I used to have that, back in public school. Its like chemistry, physics and biologi rolled into one. [editline]9th January 2012[/editline] [QUOTE=ButtsexV3;34126206]Honestly, I'm sort of afraid of quantum computing. Not because I don't think it would be a good thing, but because I'm afraid they'd have to break the x86 trend to feasibly do it. I'm afraid that nothing we have now would work on quantum computers. Of course it's possible that I just don't understand quantum computing or the x86 instruction set as well as I thought I did, but there's always that possibility.[/QUOTE] [editline]9th January 2012[/editline] [QUOTE=ButtsexV3;34126206]Honestly, I'm sort of afraid of quantum computing. Not because I don't think it would be a good thing, but because I'm afraid they'd have to break the x86 trend to feasibly do it. I'm afraid that nothing we have now would work on quantum computers. Of course it's possible that I just don't understand quantum computing or the x86 instruction set as well as I thought I did, but there's always that possibility.[/QUOTE] For something this radically different, its going to break the whole x86 thing, yes. That doesnt have to be a bad thing, though, like when we went from punchcard programming to binary magnetic storage. This may be a bad analogy.

[QUOTE=T3hGamerDK;34126470] For something this radically different, its going to break the whole x86 thing, yes. That doesnt have to be a bad thing, though, like when we went from punchcard programming to binary magnetic storage. This may be a bad analogy.[/QUOTE] Quantum computers are still binary, but I'd say it's more the jump from vaccum tubes to silicon systems.

[QUOTE=ButtsexV3;34126206]Honestly, I'm sort of afraid of quantum computing. Not because I don't think it would be a good thing, but because I'm afraid they'd have to break the x86 trend to feasibly do it. I'm afraid that nothing we have now would work on quantum computers. Of course it's possible that I just don't understand quantum computing or the x86 instruction set as well as I thought I did, but there's always that possibility.[/QUOTE] Well, what sort of stuff are we worried about working? Applications probably aren't going to be a big issue- a new operating system, yes, but all the important stuff for one design-wise is already taken care of, so it would literally just be time consumed on a good chunk of nuts and bolts coding by MS/Apple and then software companies rigging up some new versions of your software, maybe not even considering there would likely be compatibility modes/emulators for it.

Surely with all that additional computing power you could emulate x86 systems?

To all the people saying they learn more here than they do at school: Here, you don't learn any of the actual science, it's just a text explaining what the science does. It's a difference if you actually get to use formulas and equations and hear proper definitions, or read a news article that explains something in prosa. Of course this is more interesting because it doesn't contain all the proper definition yadda yadda you'd get at school, but it's important you hear the proper definitions atleast once.

[QUOTE=mac338;34125976]School: Today we learn about enzymes... yeah... Internet: String theory, yeah! Temporal shifts, yeah! Quantum mechanics, yeah! Applied fluid dynamics, yeah! Space, science & Sagan![/QUOTE] Enzyme study can and has saved lifes, and will continue to do so. Yet all they are are long proteins with an area in the chain where there's lots of free functional groups. Not so exciting. Since it's not so exciting you wouldn't read about it. Nobody would learn about it. We wouldn't make actual progress in things such as these. Oh yes, but we learn [I]string theory[/I] (which is a terrible model anyway).

[QUOTE=Contag;34126745]Surely with all that additional computing power you could emulate x86 systems?[/QUOTE] You need about 4 times the power of a system to emulate it at full speed, and I'm not sure that quantum computing will be that advanced for a good while.

Einstein was right. screw quantum theory

[QUOTE=Kondor58;34125491]maybe if they turn their backs[/QUOTE] I look at computers when I use them so if my PC wants to teleport around when I'm away that's alright I don't understand anything

it goes to >6000 fps on crysis on max settings but only when you blink

[QUOTE=T3hGamerDK;34126470]I used to have that, back in public school. Its like chemistry, physics and biologi rolled into one. [/QUOTE] More accurately, it's like chemistry, physics and biology dumbed down enough so that they can fit all in one textbook.