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World's Smallest FM Radio Transmitter Created With Graphene

minty3 writes "The team used graphene's mechanical 'stretchability' in order to create a voltage controlled oscillator (VCO) – an electronic component that can generate an FM signal. The VCO was used to send and receive audio signals of 100 megahertz. The team used pure tones and more complex music signals to tune the VCO's output and found that both kinds of signals could be 'faithfully reproduced' by an ordinary radio receiver."

60 comments

  1. *world's smallest VCO by Joining+Yet+Again · · Score: 1

    Is the size of the VCO a big deal in manufacturing of any radio transmitter?

    1. Re:*world's smallest VCO by drinkypoo · · Score: 2, Insightful

      Is the size of the VCO a big deal in manufacturing of any radio transmitter?

      Only for people interested in listening in on other people without their knowledge. I can't imagine anyone wanting to do that, though. Besides, you'd need a barely visible microphone to make it useful.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    2. Re:*world's smallest VCO by Thanshin · · Score: 4, Interesting

      The world will change once someone builds a quad-copter with microphone and radio transmitter, all fitting in a 0.1mm cube.

      Politicians will have to never, ever, ever, say what they think.

    3. Re:*world's smallest VCO by Joining+Yet+Again · · Score: 1

      I'm happy to be viciously corrected by anyone who's done the sums, so... could a low power radio transmitter be powered by the very sound waves which are being picked up? Tiny microphone, tiny VCO+amp, tiny transducer -> everlasting bug.

    4. Re:*world's smallest VCO by Thanshin · · Score: 1

      It essentially depends on weak a sound you want to hear.

      It may be better to make it solar powered.

    5. Re:*world's smallest VCO by Anonymous Coward · · Score: 0

      There are some pretty obvious positive applications of this as well though, as someone who records neural signals from awake behaving animals I'd give an arm and a leg (not mine, of course) to get a wireless transmitter small.

    6. Re:*world's smallest VCO by SuricouRaven · · Score: 1

      Because the fly on the wall is still too noticeable. We need the flea on the wall.

    7. Re:*world's smallest VCO by fuzzyfuzzyfungus · · Score: 2

      Because the fly on the wall is still too noticeable. We need the flea on the wall.

      If anybody is going to fulfill DARPA's request for hybrid electronic/biological cyborg surveillance insects, they'll need some pretty tiny electronic gear....

    8. Re:*world's smallest VCO by wbr1 · · Score: 3, Insightful

      You don't even need this when most people willingly carry a remotely accessible microphone and transmitter in their pocket.

      --
      Silence is a state of mime.
    9. Re:*world's smallest VCO by Joce640k · · Score: 1

      Politicians will have to never, ever, ever, say what they think.

      Other possibility: Stop hiring politicians who think things like that.

      PS: How about a link to an article that actually tells us the dimensions of the "smallest transmitter" and some of the the science behind it, not some news aggregator whose other headlines are things like, "3 Signs Your Relationship is in Trouble".

      --
      No sig today...
    10. Re:*world's smallest VCO by Muad'Dave · · Score: 1

      The actual size might not be a big deal, but if the atomically thin size provides better thermal stability or phase noise, then it's a major win regardless.

      --
      Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
    11. Re:*world's smallest VCO by lapm · · Score: 1

      How do you know they haven't done that all ready? What we see in civilian side is always few years back from Military/Super secret spy stuff. You dont think army spends all that money just for guns and ammunition do you?

    12. Re:*world's smallest VCO by CanHasDIY · · Score: 2

      You don't even need this when most people willingly carry a remotely accessible microphone and transmitter in their pocket.

      Except that the people willingly carrying microphones and transmitters aren't the people they need to be listening to.

      --
      An enigma, wrapped in a riddle, shrouded in bacon and cheese
    13. Re:*world's smallest VCO by Anonymous Coward · · Score: 0

      To be fair, I think it might be impossible for somebody not to say something in the course of a year that offends more than 50% of the electorate.

    14. Re:*world's smallest VCO by n1ywb · · Score: 1
      --
      -73, de n1ywb
      www.n1ywb.com
    15. Re:*world's smallest VCO by sjames · · Score: 1

      You don't think people would want a compact all bands cellphone with a cheap efficient transmitter?

    16. Re:*world's smallest VCO by Anonymous Coward · · Score: 0

      Leon Theremin could be happy...

    17. Re:*world's smallest VCO by rot26 · · Score: 1

      Big fleas have little fleas on their backs, which bite 'em. And so on and so on, ad infinitum.

      --



      To ensure perfect aim, shoot first and call whatever you hit the target
  2. 100 Mhz audio? by radaos · · Score: 5, Insightful

    Audio signals of 100 megahertz? They have perfected ultrasound then.

    1. Re:100 Mhz audio? by Anonymous Coward · · Score: 0

      Don't get carried away

    2. Re: 100 Mhz audio? by Anonymous Coward · · Score: 0

      Right!
      100 MHz is radio Frequency not audio. the wording in article should read 100 MHz RF .

    3. Re: 100 Mhz audio? by Kythe · · Score: 1

      Technically, it COULD be used to produce an ultrasonic signal, but since we're talking about a VCO, not a transducer, and since those frequencies are more often used for radio, I'm not sure why you'd describe it as an "audio" signal in any case.

      --

      Kythe
    4. Re: 100 Mhz audio? by Kythe · · Score: 1

      Reading the article more carefully, I'm guessing they used ultrasonic transducers for testing purposes. However, 100 MHz would obviously be used more often as a radio carrier.

      --

      Kythe
    5. Re: 100 Mhz audio? by Joce640k · · Score: 1

      Right!

      Whoosh!

      --
      No sig today...
    6. Re:100 Mhz audio? by Fnord666 · · Score: 1

      Audio signals of 100 megahertz? They have perfected ultrasound then.

      Given that they have "faithfully reproduced" the audio by using an ordinary radio receiver and that 100MHz is in the commercial FM broadcast band, it would be reasonable to assume that 100MHz is the carrier frequency being used.

      --
      'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
    7. Re: 100 Mhz audio? by Anonymous Coward · · Score: 0

      You must be some kind of engineer. You are correct!
      100 MHz is a radio frequency near the end 107.9 MHz of the FM broadcast dial . Journalist have much to learn , quoting 100 MHz is same sentence as audio is wrong!

    8. Re:100 Mhz audio? by Anonymous Coward · · Score: 0

      Yes, even with the typo in that sentence (or poor wording) it is trivial to decode the meaning. It's a audio signal imposed on a 100 MHz carrier. That's how an FM transmitter works.

      The attitude in the GP post of feeling superior for sarcastically pointing out someone minor mistake is not going to make people think you are smart. Don't mod up people for just being an asshole.

      This is actually a very interesting advance and useful for once, but the top rated post is just some anti-social smart ass being a jerk because a science journalist screwed up as usual.

    9. Re:100 Mhz audio? by bill_mcgonigle · · Score: 1

      The attitude in the GP post of feeling superior for sarcastically pointing out someone minor mistake is not going to make people think you are smart. Don't mod up people for just being an asshole.

      QFT.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    10. Re:100 Mhz audio? by magic+maverick+ · · Score: 1

      You've got a strange name there Mr 666. You trying to be edgy or something? But I can't help but think that you're not a nice person, whenever I see your name I get all upset.

      --
      HELP MY ACCOUNT HAS BEEN HACKED BY AN ILLIBERAL ART STUDENT SET TO DESTROY THE INTERWEBZ!
    11. Re: 100 Mhz audio? by sjames · · Score: 1

      The graphene has a natural frequency that is changed by mechanical tension (like a guitar string). They tuned it to 100MHz. Then, an audio transducer modulated the mechanical tension (and so, the frequency of the graphene) to produce an FM radio signal.

  3. The actual size by Thanshin · · Score: 2

    Strange to claim it's the "World's Smallest" and not give it's size.

    I'd guess 4m x 10m?

    1. Re:The actual size by Thanshin · · Score: 1

      I meant micrometers. For some reason, /. didn't like the [micro].

    2. Re:The actual size by Anonymous Coward · · Score: 0

      It's just false advertising then to publish it in Nature _Nano_technology... $175 for subscription or $32 for the article, nice racket they have going on.

    3. Re:The actual size by khakipuce · · Score: 0

      What strange units are these? You must use "widths of a human hair", "x football fields", "y Olympic sized swimming pools", etc.

      --
      Art is the mathematics of emotion
    4. Re:The actual size by Joce640k · · Score: 1

      Strange to claim it's the "World's Smallest" and not give it's size.

      You must be new here.

      Don't ever expect Slashdot to link to a proper article instead of a crappy news aggregator site.

      --
      No sig today...
    5. Re:The actual size by Sockatume · · Score: 1

      Looks like the superstructure is about 6x6 micron, with the oscillator in the middle being a 2-4 micron diameter circle of graphene.

      --
      No kidding!!! What do you say at this point?
    6. Re:The actual size by Sockatume · · Score: 1

      Any reasonable definition of nanotechnology simply requires that one or more component be in the nanometre range; given that the vacuum gap in the oscillator is 5-200nm depending on the device, that sounds fair.

      --
      No kidding!!! What do you say at this point?
    7. Re:The actual size by Anonymous Coward · · Score: 0

      About the size of an extraneous apostrophe in a possessive pronoun. What kind of Asperger's case are you? Can't even tell its from it's.

    8. Re:The actual size by mcgrew · · Score: 1

      Don't ever expect Slashdot to link to a proper article instead of a crappy news aggregator site.

      Don't blame slashdot, first blame the submitters -- they're the ones supplying the links. Next, blame yourself for not voting down stories with shitty links and then submitting your own with a good one.

      And since you got me to post this offtopic answer, Buy my book! Or at least read it. Just to make up for the downmod!

  4. Significant new type of oscillator by Anonymous Coward · · Score: 5, Informative

    What they have demonstrate is how a graphene structure can be made into a tunable oscillator by constructing a rather crude but working FM 'radio-transmitter' using one.

    Its significant because older mechanical oscillators were based on crystals or MEMS stuctures that are rather more 'large' than "a one atom-thick graphene sheet" and in practical applications often require considerable space and volume on a circuit board or inside a die package.

    If this structure could be incorporated into the microlithography process that is used in making 'electrics chips' then a large external component could be omitted from designs. You could also include multiple independent oscillators on the same die that requires them allowing for more precise control of frequencies needed.

    AC cause I can't be bothered to login - more Karma for dev/null ^^

    1. Re:Significant new type of oscillator by Anonymous Coward · · Score: 0

      So this could be a hopeful candidate for making a cellphone that covers all 44 of the LTE bands?

  5. I, for one, welcome.... by Anonymous Coward · · Score: 0

    ....Source Gas! (Transmetropolitan)

  6. Range? by Anonymous Coward · · Score: 0

    How much power is the device able to transmit? Sorry, but unless clicking that link funds the price of the paywall then my question will originate from the proximity of the abstract.

    1. Re:Range? by Kythe · · Score: 1

      If it's just a VCO, it would really depend on the transmit amplifier in any case.

      --

      Kythe
    2. Re:Range? by Anonymous Coward · · Score: 0

      How much power is the device able to transmit? Sorry, but unless clicking that link funds the price of the paywall then my question will originate from the proximity of the abstract

      As the other comment replied to you, this is only a VCO. It's a part of an FM transmitter and a part that where miniaturization has been limited. Power comes from the amplifiers. More power means more heat which limits miniaturization too. Anyway, I have access to the article. The supplementary section shows their experimental setup. There are a number of additional components. Bias-Ts, phase shifter, bandpass filters and an amp. The amp is a 60 dB variable gain amp. I also believe the signal was fed directly into the FM receiver and not transmitted via an antenna, because that's how the figure is drawn in the paper, but I'm not 100% sure on that point.

  7. Comming soon! by Anonymous Coward · · Score: 0

    To a CIA implanted tooth near you. Very near.

  8. Supplementary information by martyb · · Score: 3, Interesting

    What they have demonstrate is how a graphene structure can be made into a tunable oscillator by constructing a rather crude but working FM 'radio-transmitter' using one.

    You are correct. And crude is an apt choice of wording... From the supplementary information (scroll to the bottom), there are links to: pdf containing data on setup, testing, and characterization as well as a .wav file (confusingly labeled "movie"). It appears to be a sample of a transmitted sound sample of "Gangnam Style!"

    The sound quality of this sample is more on the order of a noisy AM radio broadcast, but given the technology being used, quite impressive, nonetheless.

    FWIW, there is a (somewhat) better write-up at redorbit.

    And, yes, the 100MHz in TFS refers to the carrier frequency, which is but one of several that they tested. But, it also happens to be in the FM radio band and hence the (attention-grabbing) title.

    1. Re:Supplementary information by TheCarp · · Score: 1

      > It appears to be a sample of a transmitted sound sample of "Gangnam Style!"

      And another opportunity to Rickroll entire communities is lost.

      --
      "I opened my eyes, and everything went dark again"
  9. Imagine a beowulf cluster of these by Anonymous Coward · · Score: 0

    yeah yeah old meme

    But what if tuneable array?

  10. Cool but... by shellster_dude · · Score: 2

    Wake me up when they have created the world's smallest graphene violin!

  11. The power of graphene by Applehu+Akbar · · Score: 1

    So this is what brings us those tiny PBS relay stations we briefly encounter in a cross-country drive?

  12. Link to article not advertising by Anonymous Coward · · Score: 0

    The actual article is at http://engineering.columbia.edu/smallest-fm-radio-transmitter-0
    The link posted in the slashdot article links to an annoying advertising site that eventually demands you watch an ad!
    I'd call that original articles link SPAM.

  13. We've been had by Anonymous Coward · · Score: 0

    That photo clearly shows a square of chocolate. We've been had.

  14. Finally! by havana9 · · Score: 2

    We can broadcast the world's saddest song on the world's smallest violin with the smallest FM transmitter!

  15. Tinfoil hat time by vlueboy · · Score: 1

    Think of the implications this can have for us with the NSA bundling it. I wouldn't be surprised if this similar tech is already snooping on us.
    No amount of de-wiring the obvious attack points will help. Seriously, the world is getting extremely inconvenient to live in when it comes to computing we can trust.

  16. Phase Noise by Anonymous Coward · · Score: 0

    If FM broadcast is their goal, then phase noise will be their fight. Small VCOs generally have notable worse phase noise than their larger counterparts. Too much, and it eats into the usable modulation bandwidth for the actual signal.

    It's probably not great since this seems to be sort of "brand new". There have been tons of graphene related electronic devices, and none of them have swept the market quite like everyone likes to think they will.

  17. Smart dust by Anonymous Coward · · Score: 0

    Cloud computing for real.

    Patent pending - Anonymous Engineering. ;-)

  18. #BadBios by Anonymous Coward · · Score: 0

    and yet you scoff...