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Supercomputing Science

Optical Transistor Made From Single Molecule 92

Posted by Soulskill
from the moore-refuses-to-surrender dept.
An anonymous reader writes "Researchers from ETH Zurich have recently managed to create an optical transistor from a single molecule in what is yet another important achievement on the road to quantum computing. The molecule itself is about 2 nanometers in size, much smaller than standard transistors, which means that a lot more could be integrated in a single chip. Dr. Hwang, lead author of the academic paper, said, 'Our single-molecule optical transistor generates almost negligible amount of heat. When a single molecule absorbs one photon, there is some probability (quantum yield) that the molecule emits a photon out. The rest of the energy absorbed turns into heat in the matrix. For the case of the specific hydrocarbon molecule that we use, the quantum yield is near 100%. So almost no heat is generated.'"
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Optical Transistor Made From Single Molecule

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  • by TapeCutter (624760) * on Tuesday July 07, 2009 @11:04AM (#28608423) Journal
    ...is generated by the transitor but the compressor needed to keep it at 1.4 Kelvin will keep your basement nice and warm.
    • Not at all the thing for mobile applications, and likely a stretch even for mid sized systems. If, though, you had a really big job, it might actually be more, or even substantially more, efficient to keep a very very low power chip extremely cold than keep a very very high power chip modestly cool.
    • But will i be able theorize that one could time travel within their own lifetime, so I can step into the Quantum Leap accelerator and vanish?
  • ... but can it run Crysis? I'm not much of a physicist, but this sounds like exciting news. I'm not really clear on how a single molecule can have properties similar to a transistor though. Gotta cool it down to 1.4 K though, ouch.
    • Re: (Score:3, Funny)

      by noundi (1044080)
      Really? You're not clear on how a single molecule, consisiting of electrons, protons and neutrons, can have properties similar to a transistor, meaning it works as a simple AND operator, but you know what 1.4 K is? Where did you go to school young man?
      • by selven (1556643)
        1.4K? Isn't 1400 degrees enough to melt copper?
        • He, if the K stands for thousands then the number is a unit-less quantity, thus making your snarky comment unintelligible. So, where did you go to school? :-p

        • No, silly. You need to cool it down to 1.4 kilograms. How ones does that, though, I have no idea.
          • by N Monkey (313423)

            No, silly. You need to cool it down to 1.4 kilograms. How ones does that, though, I have no idea.

            Simple. Pack it in ice and and then accelerate it to 0.9999*c :-)

    • by Sir_Lewk (967686)

      Don't worry. Something tells me you're not quite the target audiance at this point ;)

  • Does anyone know when this science will be taught in universities?
    • Re: (Score:3, Insightful)

      by dwieeb (1573153)
      Probably when universities start caring about education.
    • I'm was actually looking for a more serious response.

      I think electronics will be the past in less than 20 years.

      • by noundi (1044080)

        I think electronics will be the past in less than 20 years.

        I'm very curious to know what you mean by that statement.

    • by fuzzyfuzzyfungus (1223518) on Tuesday July 07, 2009 @11:13AM (#28608585) Journal
      Based on These results [google.com] I'd say "several years ago".
    • by Gat0r30y (957941) on Tuesday July 07, 2009 @11:14AM (#28608601) Homepage Journal
      I took a biophotonics course at university. The reason they don't teach this much: its dense, and extremely difficult. While the equations might look pretty in Transmission / Waves class, when you actually get down to the scale of molecules and the like, with all of the complications that entails, it is virtually impossible to make meaningful sense of the mathematical results. The best you can do is a computer simulation, which is occasionally useful, and of course test in the lab.
      • by castironpigeon (1056188) on Tuesday July 07, 2009 @11:33AM (#28608883)
        In other words, either we're reaching the limit of what traditional education can teach to a person in a reasonable amount of time or we're reaching the limit of human comprehension. At least one of the two will need a major overhaul before we'll see molecular transistors and biophotonics reach the level of accessibility and acceptance of, say, amateur electronics. And until that happens we'll only see slow, fringe, theoretical progress like this.
        • by Anonymous Coward on Tuesday July 07, 2009 @11:59AM (#28609269)

          Well, do you have a detailed understanding of the equations involved in avalanche breakdown of semiconductors and so on?

          But it doesn't matter. You just plug in the appropriate zener diode, or transistor or whatever, that do things in a certain way, that we can understand, but how or why it behaves that way, we don't need to know in order to use it effectively.

          • Re: (Score:3, Insightful)

            The chap who designed the "appropriate zener diode, or transistor, or whatever" may well have had to understand avalanche breakdown.

            Loads of stuff can be used with relatively limited knowledge, which is great; but that doesn't obviate the need for the knowledge of how they work.
            • by BlueTooth (102363)

              ...Yes, specialization marches on as the key to technological advances.

            • by bkpark (1253468)

              The chap who designed the "appropriate zener diode, or transistor, or whatever" may well have had to understand avalanche breakdown.

              Loads of stuff can be used with relatively limited knowledge, which is great; but that doesn't obviate the need for the knowledge of how they work.

              On the other hand, there are such things as accidental discoveries. If I remember correctly, for the first few decades that we have been making transistors, no one could explain, from basic physical principles, why they work the way they do.

              Nonetheless, people knew how to make them (i.e. how to dope the substrates in a particular way and combine them) and they knew how they would work. Knowing why they work that way was, well, simply not required, even for the people who took out patents on the device.

              I bel

            • Some how I don't think so.

              Many times novel properties of materials are discovered by accident. Far more fundamental discoveries are preceded by, "That's odd..." rather than "Eureka! I found it!"

        • by MozeeToby (1163751) on Tuesday July 07, 2009 @12:27PM (#28609727)

          Education isn't about learning every detail about the job you're going to do about graduation. At least a good education isn't. A good college will give you a strong background in an area you wish to pursue, a strong work ethic, but most importantly, it will teach you how to learn. A modern education's primary goal must be to teach the students how to look up and assimilate information on their own.

          When you hit an issue at your job, you don't just run to a more experienced co-worker anymore (which was the standard behavior 20 years ago). You look it up online, you read and learn from what you find, then you make a simple project to test out what you've learned. Beyond the very basics of your profession, those are the skills that matter most because those are the skills that produce results when no one else has the answers.

          • Re: (Score:2, Insightful)

            by 7n7 (904933)

            You look it up online, you read and learn from what you find, then you make a simple project to test out what you've learned.

            It is extremely sad how many "developers" can't do this very thing.

            TNT

    • by Bakkster (1529253)

      Does anyone know when this science will be taught in universities?

      My university has a Photonics concentration within the Electrical Engineering degree program.

      As for learning this kind of cutting-edge stuff, that would happen in a graduate or post-grad program, just like any field.

  • OK, so clue me in (Score:1, Interesting)

    by Anonymous Coward

    If one photon is absorbed and one emitted where does the heat energy come from. The molecule must be absorbing more than one photon, or is it also being "powered" so that the absorbtion can take place?

    • Re:OK, so clue me in (Score:4, Informative)

      by Nadaka (224565) on Tuesday July 07, 2009 @11:09AM (#28608501)

      either:
      a: the photon is released has a longer wavelength and thus less energy.
      b: the rate is "nearly" 100%, as in sometimes it absorbs a photon and produces heat.

    • Re:OK, so clue me in (Score:4, Informative)

      by SlashDotDotDot (1356809) on Tuesday July 07, 2009 @11:09AM (#28608513) Journal

      If one photon is absorbed and one emitted where does the heat energy come from. The molecule must be absorbing more than one photon, or is it also being "powered" so that the absorbtion can take place?

      I think he's saying that the molecule either releases a photon or heat is generated. In this case there is a high probability that for the photon release, so heat generation is rare.

      • Heat is an electromagnetic phenomenon, so wouldn't that involve a released photon as well?
        • by 2names (531755)
          Not necessarily. I'm sure you've noticed the heat produced when you furiously rub your pecker, but have you ever seen it glow?
        • Heat is an electromagnetic phenomenon, so wouldn't that involve a released photon as well?

          No, heat is a form of energy. Electromagnetic radiation is also a form of energy. You can convert energy from one form to the other, such as heating an object by shining light on it, or that same object radiating visible light when it gets hot enough, but they aren't the same phenomenon.

      • by rcamans (252182)

        Actually, if the photon released is a different frequency than the one absorbed (lower frequency, less energetic), then the energy difference is transformed into heat (movement energy of the atom). The atom will speed up a little. Or the electrons jump out to a higher energy level.
        If the photon released is a higher frequency than the one absorbed, the atom will cool of, slow down, or the electrons will drop into a lower energy state.

    • by nedlohs (1335013)

      Do you know what "there is some probability" means?

      Hint, it doesn't mean "always".

  • by idontgno (624372) on Tuesday July 07, 2009 @11:07AM (#28608477) Journal

    We've made a quantum optical transistor out of a single molecule!

    The bad news is that the single molecule masses about 2.4 tonnes. Yeah, it's a pretty big molecule. And don't scuff it, either. We don't want to brush any carbon atoms off the surface.

    • We've made a quantum optical transistor out of a single molecule!

      The bad news is that the single molecule masses about 2.4 tonnes. Yeah, it's a pretty big molecule. And don't scuff it, either. We don't want to brush any carbon atoms off the surface.

      That's quite possible, you know. Bowling balls are single molecules. Almost any macromolecule can be made arbitrarily large with cross linking.

      • Re: (Score:3, Interesting)

        by Nadaka (224565)

        Bowling Balls are not single molecules. They are constructed with a weighted core surrounded by a polymer resin.

        However, pure crystals are technically very large molecules. And they can get very large.

        • Bowling Balls are not single molecules. They are constructed with a weighted core surrounded by a polymer resin.

          However, pure crystals are technically very large molecules. And they can get very large.

          Okay, I was thinking of old rubber balls. Still, in more modern balls the resin is a single molecule.

  • Leakage (Score:5, Interesting)

    by Canazza (1428553) on Tuesday July 07, 2009 @11:12AM (#28608561)

    do quantum transistors suffer from leakage? if so, while this is an excellent piece of engineering on it's own, it's pretty useless in practice as any data would just get lost in the fudge.

    Everything in the article focused on the heat loss, energy efficiency and potential throughput, but no reasons were specifically given as to why this would succeed where Electronic processors have broken down other than 'Photons are beter than Electrons'.
    How close can these new transistors get before they start contaminating each other's states?
    Would these not be more suceptable to outside interference (Stray cosmic rays, shining a torch on it?)

    Okay, maybe not the shining a torch on it. But if a single molecule transistor is hit by a stray photon, it *will* affect it's state surely. If so are they going to have abour 20 transistors doing the calculations and matching them for discrepencies?

    The article raises more questions than it answers. Maybe I just don't know enough about quantum computing, but I'd like the answers all the same.

    • Re:Leakage (Score:5, Informative)

      by Bakkster (1529253) <Bakkster@man.gmail@com> on Tuesday July 07, 2009 @11:35AM (#28608913)

      do quantum transistors suffer from leakage? if so, while this is an excellent piece of engineering on it's own, it's pretty useless in practice as any data would just get lost in the fudge.

      Well leakage in electronic circuits comes from current flowing through the semiconductor while it is in an "off" state. Quantum photonics doesn't deal with current (or even electricity), so there would not be the same kind of leakage. I'm not aware of a comparable phenomenon specific to quantum states, but I'm just an EE, so some physicist might prove me wrong.

      Everything in the article focused on the heat loss, energy efficiency and potential throughput, but no reasons were specifically given as to why this would succeed where Electronic processors have broken down other than 'Photons are beter than Electrons'. How close can these new transistors get before they start contaminating each other's states? Would these not be more suceptable to outside interference (Stray cosmic rays, shining a torch on it?)

      Okay, maybe not the shining a torch on it. But if a single molecule transistor is hit by a stray photon, it *will* affect it's state surely. If so are they going to have abour 20 transistors doing the calculations and matching them for discrepencies?

      First of all, photons are better than electrons for the reason I gave above, and because all of our long-distance and high data-rate information transmission is already optical. Instead of going from light to silicon and back, sticking with light reduces latency. It also improves efficiency, as the photon's energy is harnessed to perform the switching.

      As for interference, if the molecule only responds to photons, shielding it from outside photons is trivial. It's called a box. I also get the impression FTA that the output of the transistor is well controlled, meaning that interference could be minimized or removed completely very easily.

      The article raises more questions than it answers. Maybe I just don't know enough about quantum computing, but I'd like the answers all the same.

      When has any quick article about a new tech breakthrough given all the answers?

      • by Khashishi (775369)

        As for interference, if the molecule only responds to photons, shielding it from outside photons is trivial. It's called a box. I also get the impression FTA that the output of the transistor is well controlled, meaning that interference could be minimized or removed completely very easily.

        Of course, any meaningful computer will have more than thousands of these transistors, and surrounding every transistor with a box is far from practical. And, consider, once you shrink a box down to nanometer sizes, it will become leaky.

        • by Bakkster (1529253)

          Well, in this case we're talking about lasers traveling through a crystal and being turned on and off with another laser. Unlike electrons and holes in a semiconductor (which drift and move around, causing leakage current), lasers travel in a straight line until they are made to change direction. The laser paths could even cross without interfering with each other.

          The only issue I can imagine is scattering, due to dust (practically non-existent in cleanroom manufacturing of this quality) or the transisto

    • by rcamans (252182)

      photons do not suffer from the issues of signal loss, signal quality, partial reflections, waveform distortion, EMI/EMC, crosstalk, noise, etc. electrons / holes do. Whole regions of current electronic simulation issues go away.
      New ones open up.

  • by Peteskiplayer (1032662) on Tuesday July 07, 2009 @11:14AM (#28608591)
    So does that mean we'll finally get Tron-esque glowing computer parts?! ..I'm guessing it depends on the energy level of the photons and the frequency they are released.. but please let them be a soothing blue :) In all seriousness, this sounds excellent, good job guys.
    • by peragrin (659227)

      Well glowy computer parts are cool but I would rather have an optical router and network cards. Fiber to the home.

      • by ae1294 (1547521)

        Fiber to the home

        You'll get your fiber to your home in a few years but your internet speed will still be locked at 10/10Mbps. The rest of the bandwidth will be used for pay-per-view and other services as deemed by your local monopoly. O and you'll still be using ipv4 because it would cost a little money upgrade to 6 and they wouldn't want you to have more than 1 IP anyhow, at least not without spending $400 on a business account. O and No static addresses ether... And port 80 among others will still be filtered. It's all fo

        • 10/10Mbps?
          10/0.5Mbps surely...

        • by Zakabog (603757)

          I had fiber (FiOS) at my home three years ago, port 80 was the only port blocked to my house and I had 40/10Mbps. When I switched to business (since I actually was attempting to run a hosting business out of my home and needed the 5 static IP addresses) it was only an extra $80 a month plus I increased my speed to 50/20Mbps. It was reliable, very fast, and cheap for the bandwidth provided compared to the other options (cable was something like 5/0.5Mbps for the same price as 40/10Mbps FiOS and DSL was even

        • Nah. WiMAX routers will be at $100 a piece, reaching over 20 miles, and you will have a network with all the other WiMAX routers, giving you a failsafe, multirouting, and encrypted (to the server) connection for "free" (except for the power and the router itself).
          Maybe some will offer a city backbone, to reduce the hops to the next major CIX node.

      • by popeye44 (929152)

        Yea, good luck with the fiber to the home. I have a nice fiber right up to my cabinet on the side of my house.. no one in town will use it. ATT Uverse still wants to use copper. Idiots. Of course Verizon can't come in because it's an ATT area. Frankly Competition sucks for FTTH. So I'm stuck with cable.. which isn't too bad I guess "16/2" but they could do more over the fiber. They don't have any plans either.

        Now as far as Quantum Computing goes.. I know about enough to fill a molecule with room for a large

    • Yes! Wham-O is already working on a glowing frisbee using these.
    • As long as they pass a law banning the posession of these devices by anyone over 200 lbs. Ugh.
    • by N1ck0 (803359)
      The down side is if the photon emitted by the molecule is visible to you, it couldn't have be properly passed to the next optical transistor....

      okay it could but:
      1. you would have to be entangled
      2. make sure noone observes you seeing the photon
      3. Don't make any sort of measurement or acknowledge that you saw the photon

      Otherwise you could either see the light from the processor or the processor would work properly...it couldn't do both. :)
      • The down side is if the photon emitted by the molecule is visible to you, it couldn't have be properly passed to the next optical transistor....

        True, but not always a problem. Consider an AND gate. Ideally, this would emit a photon when it absorbs two photons, and not emit a photon when it absorbs a single photon. In both of these cases, it is absorbing one more photon than it is emitting. This will cause it to get warm. Alternatively, it could emit the spare photon directly upwards away from the die. In this case, you would see the chip flickering quickly.

        Of course, this doesn't apply to all gates.

    • by chogori (1514025)
      I think for that pleasing blue glow it's important that we transmit the photons faster than the speed of light in the transmission medium so that they blue shift.

      Kind of like that great blue hue you get on an out-of-control nuclear reactor when atomic particles are hitting the coolant at speeds faster than the speed of light in water [wikipedia.org].
  • but only because some of the photon bombardment results in actual vaporization of the technology in question

    so we need a new word, in regards to nanotech, for the traditional connotation of vaporware meaning technology that is announced but will not be realized. something that has nanotech connotations

    hmmm. perhaps sevenofnineware. because you most certainly are out of that league

    • by maxume (22995)

      Fantasyware seems like a good enough name for unrealized nanotech. The confusion that would arise with the realization of some nanotech would be a side benefit.

  • Going a bit further in time with this kind of molecules, how them can be used in mass production of quantum computers, if there will be any of such in the future? Genetic engineering?
  • This just blows my mind away, the leaps and bounds that can be made with just a few of these emergent techs is, is.... WOW! While I have never been one completely on the tail of Kurzweils futurism visions of the singularity, this is one step closer to that vision, right? I mean, seems to me that the power of computing with this technology will help us approach that figure where the interconnecting happening within our CPU cycles gets near the same 'mass' as whatever it is that happens in our grey matter
  • http://dx.doi.org/10.1038/nature08134 [doi.org]
    Couldn't find anything in TFA or at ETH's website. Luckily, it was in a journal who's RSS feed I subscribe to!
  • Hehehe... this incredible stuff gets me thinking about theories related to Area-51 and technologies from crashed extra-terrestrial alien spacecraft and stuff. Go back in your mind as few as 25 years ago (if you are old enough) and imagine how you would have reacted if such technologies emerged at that time "out of the blue."? I think the reaction would be quite startling. Hell, even 25 years ago there were some pretty amazing developments and the like. But this is pretty awesome stuff. I'm still waitin

    • Not sure about 25 years ago. The first I saw about optical processing was 15 years ago, and this was in the mainstream press so research had been going on for a while. The advantages of optical processing are obvious once you design a nontrivial electronic circuit; photons can pass through each other without interacting, so you don't need to make sure the wires never cross, while electrons can't. Getting photonic circuit elements down to a single molecule is very difficult to do, but not difficult to ima

      • by erroneus (253617)

        Yeah but this thing with using molecules rather than larger bits of material scaled down and all that? Pretty impressive.

  • I'm probably being dense here, but I'd really appreciate anyone who can explain how this can possibly work given that the wavelength of light is many hundreds of times longer than 2nm? I read the article and was none the wiser. Given the mention of quantum mechanics, is this related to wave/particle duality? That is, this detects the light particle irrelevant of the wavelength?

    • by sFurbo (1361249)
      The thing about the wavelength is that light can't differentiate anything smaller than the wavelength (or half the wavelength, i can't recall), but it can interact with something smaller. So, if two of these were closer than the wavelength, you can't selectively shine light on one, but you can hit both. Actually, that might be a feature, if you send in one photon, and activate one of two which are closer than the wavelength, their activation will be entangled. But I have no idea whether they plan to use tha
  • Does it run Linux?

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