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Communications Science Technology

First Room-Temperature Germanium Laser Completed 80

eldavojohn writes "MIT researchers have built and demonstrated the first room-temperature germanium laser that can produce light at wavelengths suited for communication. This achievement has two parts: '[U]nlike the materials typically used in lasers, germanium is easy to incorporate into existing processes for manufacturing silicon chips. So the result could prove an important step toward computers that move data — and maybe even perform calculations — using light instead of electricity. But more fundamentally, the researchers have shown that, contrary to prior belief, a class of materials called indirect-band-gap semiconductors can yield practical lasers.' While these are only the initial steps in what may become optical computing devices, the article paints it as very promising. The painful details will be published in the journal Optics Letters."
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First Room-Temperature Germanium Laser Completed

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  • Re: (Score:2, Insightful)

    Comment removed based on user account deletion
    • by Anonymous Coward on Friday February 05, 2010 @05:19AM (#31032872)

      Why is this better than existing solid-state lasers?

      -jcr

      Already being integrated with silicon for circuits [wikipedia.org]. And like the summary says, manufacturing is much easier.

      • Manufacturing is easier, provided you first have a stable supply of the element. In the future, rare earth elements will dominate the high tech economy. China is the world's largest producer.

        Basically, instead of the middle east having us by the short hairs, in the future it's going to be the Chinese.

        • instead of the middle east having us by the short hairs, in the future it's going to be the Chinese.

          In the future?

    • by Shadow of Eternity ( 795165 ) on Friday February 05, 2010 @06:09AM (#31033052)

      Stronger, faster, more efficient.

      Downside is it has a tendency to encroach on polandium lasers...

    • by jank1887 ( 815982 ) on Friday February 05, 2010 @07:45AM (#31033446)

      lasers compatible with silicon processing technology are a good thing. SiGe is a proven IC material set with a sort-of robust processing knowledgebase. Incorporating Germanium optics into silicon designs supposedly will usher in a new era of wacky computing with on-chip optical logic elements, interconnects, etc. Some people think quantum computing would be easier if you were working in the optical instead of electrical domain. Blah blah. People made silicon lase not too long ago, but efficiency was horrible. Germanium can make for a much better optics, and now you can put in together.

      • Re: (Score:3, Informative)

        by soundguy ( 415780 )

        Silicon has a 0.7v drop across a pn junction, whereas germanium only drops 0.3v. I would imagine that being able to use much lower operating voltage has some benefits.

    • Sharks aren't allergic to germanium, so it's safer and cheaper to mount this laser on their heads, because you don't need so much shielding. This reduced shielding also makes it easier for the shark to aim the laser, easier to swim [less drag], and more environmentally friendly.

  • But can they be attached to sharks?
    • Vacuum deposited silicon substrates anchored to the shark tend to itch; and the shark scratches that location constantly. So you need to solve the skin irritation problem before you lay down the germanium layer.
  • by ignavus ( 213578 ) on Friday February 05, 2010 @05:26AM (#31032886)

    Shouldn't Berlin University be the one using the Germanium?

    MIT should have made their laser out of Americium.

    And it sucks to be Cambridge. There is no such thing as Englandium.

    What? No, I don't have anything sensible to say about this story. And anyway, at first I thought it said geranium, and my comment was going to be even stupider than this one.

    • by dcmoebius ( 1527443 ) on Friday February 05, 2010 @05:56AM (#31033002)

      And it sucks to be Cambridge. There is no such thing as Englandium.

      England could use noble gases, perhaps?

    • Yeah, I was going to go with something about space nazis but then I thought, oh whatever.

    • by MightyDrunken ( 1171335 ) on Friday February 05, 2010 @07:22AM (#31033340)

      It does suck for the English, they could use Europium but the best I could find was Rhodium, meaning rose. The next best is Rutherfordium for Ernest Rutherford as he was a British citizen but was born a New Zealander.
      Hell even Ytterby a Swedish village has two elements named after it (Ytterbium and Yttrium).

      A few more but by no means an exhaustive list.

      • Paris (Lutetium)
      • German state of Hesse (Hassium)
      • Gaul-France (Gallium)
      • France (Francium)
      • Germany (Germanium)
      • Kobold Goblin (Cobalt)
      • California (Californium)
      • University of California, Berkeley (Berkelium)
      • Scandinavia (Scandium)
      • Nobel Institute in Sweden (Nobelium)
      • Re: (Score:1, Insightful)

        by Anonymous Coward

        Actually, Ytterby has four elements named after it: Ytterbium, Yttrium, Terbium and Erbium.

      • i'd prefer plumbum, i think it's latin for lazy arse, swinging the lead or something...
      • We are not nationalistic (because we don't need to be.) No country name on our stamps because we invented them. Davy discovered sodium and potassium (natrium and kalium) and gave them proper Latin names. Rutherford was a colonial so it was OK to name an element after him. In fact Herschel (who was partly German, which explains it) wanted to call his newly discovered planet "Siderius Georgius" after King George, but the King said "Herschel, we British don't do that kind of thing. Kindly stick it up your anu
      • Re: (Score:3, Insightful)

        Don't forget Terbium (Tb) and Erbium (Er). http://en.wikipedia.org/wiki/Ytterby [wikipedia.org]
    • by hey! ( 33014 )

      And it sucks to be Cambridge. There is no such thing as Englandium.

      I know. And the atomic symbol "Uk" is available too.

    • by pjt33 ( 739471 )

      In Cambridge they just have to use a dielemental approach which mixes carbon and americium.

    • > And it sucks to be Cambridge. There is no such thing as Englandium.

      They can use Britannium.

  • they invent a geranium laser. Green laser power in your window.

  • Cool! And I guess all you need to power it is plenty of sunlight, water and the occasional packet of Baby Bio.

  • by t0qer ( 230538 )
    Sweet ET can phone home.
  • I for one welcome our new powered-by-room-temperature-germanium-laser-optical-computer overlords
  • they were talking about photons supplanting electrons in the '80s. and it was supposed to be imminent, right around the corner

    AI, tablet computers, rocket cars, fusion power, natural speech computing:

    eternally 10 years away

    wake me up when it actually happens

    • Yes, Sleeping Beauty.

    • AI, tablet computers, rocket cars, fusion power, natural speech computing

      One of these does not belong with the others.

  • Now we need room temperature sharks

  • Er, but there's a very good reason Germanium is not used much as a semiconductor.

    It has very high leakage at room temp, and the leakage goes up exponentially from there.
    By the time you get up to 50C it's basically a poor resistor instead of a semiconductor.

    So this really is a "room temperature laser", in the sense that you have to cool it to room temperature.

  • by Anonymous Coward

    Oh dear. So many replies, so much nonsense. Slashdot these days...

    This is a great achievement.

    What is great about this laser is that they seem to have found a new
    material system that emits at communication wavelength. Communication
    wavelength are important because this is a wavelength you can couple well
    into optical fibers.

    What they seem to do is they apply tensile strain to a germanium layer and
    basically push it's energy bands from indirect semiconductor to direct
    semiconductor. Direct semiconductors can amp

  • Ge (Score:1, Funny)

    by Anonymous Coward

    you know the Germans always make good stuff.

  • by Tetsujin ( 103070 ) on Friday February 05, 2010 @01:15PM (#31037042) Homepage Journal

    bedeutet das wir endlich diesen verdammten Haie mit Lasern auf dem Kopf?

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