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Physicists Create a Working Transistor From a Single Atom

stupendou writes "Australian and American physicists have built a working transistor from a single phosphorus atom embedded in a silicon crystal. The group of physicists, based at the University of New South Wales and Purdue University, said they had laid the groundwork for a futuristic quantum computer that might one day function in a nanoscale world and would be orders of magnitude smaller and quicker than today's silicon-based machines."

11 of 127 comments (clear)

  1. Finally, a computer so small... by MrEricSir · · Score: 4, Funny

    ...it will slip between the fibers on your pocket, fall on the floor, get vacuumed up and get accidentally thrown away.

    The future is here.

    --
    There's no -1 for "I don't get it."
    1. Re:Finally, a computer so small... by Anonymous Coward · · Score: 5, Funny

      "I always mess up some mundane detail"

  2. Radiation hardening by DigiShaman · · Score: 4, Interesting

    With transistors that small, how would you harden a microchip against radiation? Would the extra redundancy not make it worthwhile. That is to say, is there an optimal compromise between transistor size and resources consumed through redundancy allocation?

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    Life is not for the lazy.
    1. Re:Radiation hardening by __aaltlg1547 · · Score: 4, Interesting

      Normal computers aren't radiation hardened, but the point is that they store and process information based on more than just the quantum state of a single particle. It takes a great deal more unwanted energy to cause them to flip to the undesired state. This kind of thing would many times more vulnerable to stray radiation, heat or stray electromagnetic fields than the smallest conventional transistor.

      But any practical computer is going to have to contain millions of these things. If you want to carry out a computation with such a machine, either you have to protect it with conditions that have a minimal chance of causing a computational error or you will have to engineer it with redundancy and error correction mechanisms that may in the end be bigger and less reliable than a classical solution.

  3. Re:A transistor made of a single atom? by artor3 · · Score: 5, Interesting

    We were making single atom transistors ten years ago, but it was hit or miss whether the atom would end up in the right place.

    Today, we can place the atom with high precision, in silicon, so that the devices can be made reliably.

    Ten years from now, who's to say we won't be able to mass produce them?

  4. Not to nay-say, but... by koolguy442 · · Score: 5, Interesting

    I hate being a nay-sayer, but the NYT article is making quite a spectacle about this whole thing. What the group has truly done is demonstrate a novel method for placing a single phosphorus atom within silicon and proceeded to measure the semiconducting properties of the resultant device with quite good precision. Because the doping is the result of a single atom, they can resolve more than just "on" and "off", and in fact can read three states from it, so it gets its quantum computing title.

    As a materials scientist, I'm worried that they don't show any long-term data and all their results appear (from my not-so-thorough reading of the originating Nature Nanotechnology report) to be based on a single device. How repeatable is this result and how consistent are the signals across multiple devices? How far will the phosphorus atom diffuse over the lifetime of the device? Or even over the first few hours of its operation at room temperature? How closely can these devices be placed to each other on the silicon chip without getting cross-interference or depriving the dopant of its discrete quantum states? The dopants in a normal device aren't too terribly close to each other. And finally, how big must the surrounding structure be?

    Don't get me wrong, this is excellent science and well deserving of its publication in such a prestigious journal, but the spectacle that the NYT is creating around this and the dreams of such a tiny device is a bit premature.

    1. Re:Not to nay-say, but... by GerhardKlimeck · · Score: 4, Informative

      The devices built in this form have been tested against temperature cycling. They have in fact traveled across continents for testing and examination. The NY times accurately reported my qualification that this cannot be mass produced (yet) and is limited to low temperatures. I see no hype in the NY Times story. I am one of the authors of the paper.

  5. Re:Mod manipulation by GreatBunzinni, aka Rui Maci by Sarten-X · · Score: 5, Insightful

    As someone who's been routinely getting "-1, Overrated" on many of my posts for about a year, I most say: Do shut up already.

    In the time it takes to downmod someone, a few people have seen the opposing post, and likely agreed, or at least posted something in response that's likely to generate more interest in the original. With the high volume of traffic Slashdot gets, even 20 accounts isn't enough to obliterate any opinion to a reasonable degree. One particularly controversial post of mine managed to get every single moderation, before ending up at "+4, Interesting". I had over a dozen "flamebait", "troll", and "overrated" mods.

    Mod gaming is a known problem. Slashdot's system is still above average in my opinion, and has the benefit of enough wide participation (and light enough consequences) that it doesn't matter. Sure, it's disheartening to see one of my deeply-thought-out statements misunderstood, but it's Slashdot. It's not like anything said here has a high probability of drastically changing the world.

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  6. Re:A transistor made of a single atom? by cold+fjord · · Score: 4, Informative

    Today, we can place the atom with high precision, in silicon, so that the devices can be made reliably.

    Cornell demonstrated a single atom transistor nearly 10 years ago, and today we are still pretty much at the level of demonstrating / playing / investigating.

    Ten years from now, who's to say we won't be able to mass produce them?

    It is a pretty big jump from building a single demonstration / proof of concept device and connecting it and integrating it into a design that works reliably at speed. IBM seems to be getting some interesting results with a single atom DRAM, but that is still way closer to a laboratory curiosity than an option for shipping silicon.

    But that is just the Fab side of things. To actually design and build chips with this sort of technology is almost certainly going to require some serious upgrades to EDA tools.

    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  7. Re:Too small by c0lo · · Score: 5, Funny

    I want steam based computing. Big things lots of spinning wheels and whistles. Down with this mamby-pamby micro electronics.

    Just be careful with overclocking.

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    Questions raise, answers kill. Raise questions to stay alive.
  8. Re:A transistor made of a single atom? by TheInternetGuy · · Score: 4, Funny

    Ten years from now, who's to say we won't be able to mass produce them?

    A little known fact about Moores law. People usually don't know this, but Moores law is actually an inverted bell curve, so a few years from now, circuits will actually start to grow bigger and bigger every year. In the future we will have computers as big as mt to perform the simplest tasks. Unfortunately the bottom of this bell curve occurs at the same time as the end of the Mayan calendar, so not to many people will be around to worry about it.

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    If my comment didn't sound as good in your head as it did in mine, then I guess we all know who's to blame