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First Room-Temperature Germanium Laser Completed

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."

56 of 80 comments (clear)

  1. Fill us in, please? by jcr · · Score: 2, Insightful

    Why is this better than existing solid-state lasers?

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
    1. Re:Fill us in, please? by Anonymous Coward · · Score: 4, Informative

      Why is this better than existing solid-state lasers?

      -jcr

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

    2. Re:Fill us in, please? by Shadow+of+Eternity · · Score: 4, Funny

      Stronger, faster, more efficient.

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

      --
      A bullet may have your name on it but splash damage is addressed "To whom it may concern."
    3. Re:Fill us in, please? by someone1234 · · Score: 1

      You meant polonium, right?

      --
      Patents Drive Free Software as Hurricanes Drive Construction Industry
    4. Re:Fill us in, please? by jank1887 · · Score: 4, Informative

      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.

    5. Re:Fill us in, please? by aurispector · · Score: 1

      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.

      --
      I have mod points. The reign of terror begins now.
    6. Re:Fill us in, please? by soundguy · · Score: 2, Informative

      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.

      --
      Nothing worthwhile ever happens before noon
    7. Re:Fill us in, please? by dakameleon · · Score: 1

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

      In the future?

      --
      Man who leaps off cliff jumps to conclusion.
    8. Re:Fill us in, please? by truthsearch · · Score: 1

      No, he meant bolognium, whose atomic weight is deliciously snacktacular.

    9. Re:Fill us in, please? by rossdee · · Score: 1

      and also Francium (element #87)

    10. Re:Fill us in, please? by Shadow+of+Eternity · · Score: 3, Funny

      Only the Vichi isotope is conducive to interactions with germanium, the rest react violently.

      --
      A bullet may have your name on it but splash damage is addressed "To whom it may concern."
    11. Re:Fill us in, please? by AlamedaStone · · Score: 1

      Is it too much to ask to read the summary?

      I'm on a schedule here. I don't have time to read the summary AND post comments! So which sort is this thing, another Australian contraction of freedoms or a NYCL recap of RIAA legal manouvers?

      --
      "All these years believing you're the signified monkey, only to find out you're just a big hunk of nobody cares."
    12. Re:Fill us in, please? by davester666 · · Score: 1

      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.

      --
      Sleep your way to a whiter smile...date a dentist!
    13. Re:Fill us in, please? by Hillgiant · · Score: 1

      And I thought it was only suitable for popping giant balls of popcorn.

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      -
    14. Re:Fill us in, please? by steelfood · · Score: 1

      Stronger, faster, more efficient.

      On the other hand, it has no wireless and not as much space as a Nomad.

      --
      "If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
    15. Re:Fill us in, please? by Pictish+Prince · · Score: 1

      Stronger, faster, more efficient.

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

      Wow, Godwin's Law didn't waste any time kicking in here.

      --
      Only his tendency toward a dazed stupor prevented him from screaming aloud.
  2. Ah Yes... by PiAndWhippedCream · · Score: 1, Funny

    But can they be attached to sharks?

    1. Re:Ah Yes... by GaryOlson · · Score: 1

      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.

      --
      Every mans' island needs an ocean; choose your ocean carefully.
  3. Make mine from Ruritanium by ignavus · · Score: 5, Funny

    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.

    --
    I am anarch of all I survey.
    1. Re:Make mine from Ruritanium by dcmoebius · · Score: 5, Funny

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

      England could use noble gases, perhaps?

    2. Re:Make mine from Ruritanium by outsider007 · · Score: 1

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

      --
      If you mod me down the terrorists will have won
    3. Re:Make mine from Ruritanium by Shadow+of+Eternity · · Score: 1

      You could always say that a germanium laser is great because it doesn't require electricity, it runs without any juice...

      --
      A bullet may have your name on it but splash damage is addressed "To whom it may concern."
    4. Re:Make mine from Ruritanium by MightyDrunken · · Score: 4, Insightful

      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)
    5. Re:Make mine from Ruritanium by hey! · · Score: 1

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

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

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
    6. Re:Make mine from Ruritanium by Anonymous Coward · · Score: 1, Insightful

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

    7. Re:Make mine from Ruritanium by vegiVamp · · Score: 1

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

      They can use Britannium.

      --
      What a depressingly stupid machine.
    8. Re:Make mine from Ruritanium by subbydubbydoo · · Score: 1

      i'd prefer plumbum, i think it's latin for lazy arse, swinging the lead or something...

    9. Re:Make mine from Ruritanium by pizza_milkshake · · Score: 2, Insightful

      Don't forget Terbium (Tb) and Erbium (Er). http://en.wikipedia.org/wiki/Ytterby

    10. Re:Make mine from Ruritanium by Goaway · · Score: 1

      Also Yttrium and Ytterbium.

    11. Re:Make mine from Ruritanium by steelfood · · Score: 1

      I would not want to be in that lab when the laser fires.

      --
      "If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
    12. Re:Make mine from Ruritanium by thexray · · Score: 1

      Don't forget Yttrium (Y) and Ytterbium (Yb).

  4. Re:Germanium Laser? by Anonymous Coward · · Score: 1, Funny

    blah blah sharks etc etc dead horse etc blah

  5. I'll be impressed when by lxs · · Score: 1

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

    1. Re:I'll be impressed when by hey! · · Score: 1

      I'll be impressed because they'll need coherent geraniums. (er... geranii?)

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
    2. Re:I'll be impressed when by Sique · · Score: 1

      gerania.

      --
      .sig: Sique *sigh*
  6. Geranium Laser? by Rik+Sweeney · · Score: 1

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

    1. Re:Geranium Laser? by chromas · · Score: 1

      and the occasional packet of Baby Bio

      A diaper?

  7. ET by t0qer · · Score: 1

    Sweet ET can phone home.

  8. In this case, by brunokummel · · Score: 1

    I for one welcome our new powered-by-room-temperature-germanium-laser-optical-computer overlords

    --
    What is best in life? To crush your enemies, to see them driven before you and to hear the lamentations of their women.
  9. Re:Germanium Laser? by hey! · · Score: 1

    You miss the point.

    At last, we can lase about in a comfortable, shirtsleeves environment.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  10. ah yes, photonic computing by circletimessquare · · Score: 2, Interesting

    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

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    1. Re:ah yes, photonic computing by vegiVamp · · Score: 1

      Yes, Sleeping Beauty.

      --
      What a depressingly stupid machine.
    2. Re:ah yes, photonic computing by steelfood · · Score: 1

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

      One of these does not belong with the others.

      --
      "If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
  11. yes, it would be by circletimessquare · · Score: 3, Interesting

    it would be cool. it would have no resistance. and it would be faster

    so no heat sink problems, it would run at much lower power levels, and optical computing would make today's fastest electronic computers look like a texas instruments calculator from the 1970s

    additionally, since we're running fibre everywhere today, there's no real interface/ translation between the photon on the line and the photon going into the processor, ideally. the promise is that the internet would become this woven intelligent network, soaring into the stratosphere in terms of speed, interconnectivity, intelligent routing, etc. it would really open up some amazing barely imaginable implications and avenues in terms of what the internet could possibly do. or maybe it would just mean 10^100 spams per picosecond ;-P

    assuming of course they tackle the bazillion fabrication issues facing the cheap, easy production of photonic computers. we're a long way away, but i hope to see a rudimentary setup before i kick the bucket

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    1. Re:yes, it would be by Dekker3D · · Score: 1

      uhm.. no photonic transistors yet?
      from wikipedia: "A completely optical computer requires that one light beam can turn another on and off. This was first achieved with the photonic transistor, invented in 1989 at the Rocky Mountain Research Center"

      of course, it could be some vandalism or something..

  12. CAm by pjt33 · · Score: 1

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

  13. Re:Germanium Laser? by MRe_nl · · Score: 1

    Think of the potential band-width of full spectrum fibre-optics.
    In a comfortable, shirtsleeves environment of course.

    --
    "Kill 'em all and let Root sort 'em out"
  14. Now we need room temperature sharks by Joe+The+Dragon · · Score: 1

    Now we need room temperature sharks

  15. Re:Germanium Laser? by hey! · · Score: 1

    This thread is starting to sound like an infomercial.

    Throw away that bulky refrigeration equipment!

    Say goodbye to those messy liquid nitrogen dewars!

    No more trekking down to crowded laboratories!

    You can enjoy wide-bandwidth germanium laser technology in the privacy of your own home!

    (Cut to testimonial): I really enjoy having my own home germanium laser set-up. I used to schlep down to the lab five times a week, and as often as not all the equipment was in use. Now I keep my room temperature germanium laser next to the couch and use it while I'm watching TV. After just three weeks I had more definition than I'd ever had before.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  16. Re:Germanium Laser? by MRe_nl · · Score: 1

    Now, at last, I too can download 15 bibles per second, in the privacy of my own home?
    Praise the Lord!

    --
    "Kill 'em all and let Root sort 'em out"
  17. er, but... by Ancient_Hacker · · Score: 1

    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.

  18. Communication wavelength by Anonymous Coward · · Score: 1, Insightful

    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 amplify light, therefore you can
    build a laser with them.

    Now if you can take this stuff and grow bragg mirrors below and above, you
    have something interesting.

    Current semiconductor lasers for communication wavelength use nasty
    material systems. For fiber optics coupling, you want surface emitting
    lasers. Those are right now incredibly hard to manufacture with the
    materials we had until now (Think producing two separate wafers and
    then joining them mechanically). So we couldn't use them. That may have
    changed.

    To sum it up: Faster internet.

  19. Ge by Anonymous Coward · · Score: 1, Funny

    you know the Germans always make good stuff.

  20. Who's Whooshing Who? by ciroknight · · Score: 1

    Curie named Polonium after Poland ("Polonia"). So the whoosh goes to you, coward.

    --
    "Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
  21. That's because we're not nationalistic by Kupfernigk · · Score: 1
    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 anus", and the name stuck.

    We also rather own the thermodynamic part of the SI system with the Watt, the Joule, and the Kelvin, not to mention the Faraday and the Newton but that's because the rest of the world was so awed by our scientific progress that they insisted.

    For non-native English readers, please insert an irony tag wherever you find most convenient.

    --
    From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
  22. gegen ein totes Pferd by Tetsujin · · Score: 2, Funny

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

    --
    Bow-ties are cool.