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Another Step Towards Graphene Semiconductors

Posted by samzenpus on from the next-step dept.

derGoldstein writes "Ars has an article up about the two latest 'papers demonstrating that, if you change the way the graphene stacks, you obtain a voltage-controlled bandgap ... Between these two papers, a fairly complete understanding of the bandgap behavior in three-layer graphene has been obtained, leaving only the challenge of making the stuff.'"

12 of 33 comments (clear)

  1. The substance that does it all by neokushan · · Score: 2, Funny

    Honestly, is there anything Graphene CAN'T do? I'm just waiting for an article to appear that states Graphene may be a cure for Cancer and AIDS rolled into one.
    And then I'm fully expecting another article stating that it's more deadly than asbestos.

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    +1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
    1. Re:The substance that does it all by Anonymous Coward · · Score: 1

      And then I'm fully expecting another article stating that it's more deadly than asbestos.

      I think you'll find that one is nanotubes.

    2. Re:The substance that does it all by neokushan · · Score: 1, Redundant

      Yes indeed, why should we bother progressing? It's just a waste of time. Better stick with what we have now, because that's going to work out better.

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      +1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
    3. Re:The substance that does it all by Chuck+Chunder · · Score: 2

      Honestly, is there anything Graphene CAN'T do?

      Yes.

      Fortunately we have lasers for those situations.

      --
      Boffoonery - downloadable Comedy Benefit for Bletchley Park
  2. 2 layer vs 3 layer by vlm · · Score: 4, Interesting

    I'm having trouble peering thru the journalist filter and not finding any other primary sources.

    To a first approximation, the point seems to be that what we used to be able to do with bi-layer two layer graphene, we can now do with tri-layer three layer graphene. Um, OK, thats nice but not "new".

    http://arxiv.org/PS_cache/arxiv/pdf/1001/1001.5213v1.pdf

    So, aside from purely theoretical "thats interesting, just for the sake of physics", what is the point? More durable, better electrical properties, easier to make (thats hard to believe), stronger, easier to customize and control the above, or what? Someone with access to Nature-Physics to read the actual papers could probably respond?

    The article is really poor because it tapdances around the important story which is what I list above.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    1. Re:2 layer vs 3 layer by John+Hasler · · Score: 2

      I'm having trouble peering thru the journalist filter and not finding any other primary sources.

      I thought it was fairly clear that this demonstrates the existence of a bandgap that cannot be attributed to substrate effects or contaminants.

      --
      Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
    2. Re:2 layer vs 3 layer by gstrickler · · Score: 4, Informative

      To a first approximation, the point seems to be that what we used to be able to do with bi-layer two layer graphene, we can now do with tri-layer three layer graphene. Um, OK, thats nice but not "new"

      No, bi-layer graphene can have a band-gap, but it's not controllable, so it can't be used to make a transistor. Conventionally stacked tri-layer graphene has the same problem. What is new is that by changing the way three graphene layers are stacked allows creating a voltage controlled band-gap, which allows for the creation of a transistor.

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      make imaginary.friends COUNT=100 VISIBLE=false
  3. Re:Graphene == dead end :-( by peragrin · · Score: 1

    That because they are missing the final step of massively heating and compressing the graphene to create diamond circuits . After that we will have crystal computers and the future will be now.

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    i thought once I was found, but it was only a dream.
  4. A tunable photodetector by John+Hasler · · Score: 1

    One group observed the photoconductivity of their graphene sheets as a function of wavelength and applied voltage. They showed that the oddly stacked three layer graphene sheets would generate a larger current for particular colors. That is, the light was exciting electrons out of bound states and into conducting states, indicating the presence of a bandgap. Furthermore, this color changed depending on the applied voltage, indicating that the bandgap was changing with the voltage.

    A voltage tunable photodector. Useful.

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    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
    1. Re:A tunable photodetector by marcosdumay · · Score: 1

      Probably just as usefull as any normal phototransistor out there.

      But this one is a transistor, and made of graphene, a material with very low electrical and thermic resistence.

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      Rethinking email
    2. Re:A tunable photodetector by John+Hasler · · Score: 2

      > Probably just as usefull as any normal phototransistor out there.

      Normal phototransistors don't have adjustable bandgaps.

      > ...a material with very low electrical and thermic resistence.

      And thus also potentially much faster than exisitng photodetectors.

      --
      Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
  5. Re:Graphene == dead end :-( by samael · · Score: 1, Informative

    They are being modded troll because it links to a goatse.cx image...

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