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First Silicon Laser

An anonymous reader writes "Since the creation of the first working laser, scientists have fashioned them from substances ranging from neon to sapphire. Silicon was not considered a candidate, because its structure wouldn't allow for the proper line-up of electrons needed to get this semiconductor to emit light. That has now changed thanks to three researchers at Brown University who have created the first directly pumped silicon laser by drilling billions of holes in a small bit of silicon using a nanoscale template."

122 comments

  1. Yeah! by ackthpt · · Score: 2, Funny
    three researchers at Brown University who have created the first directly pumped silicon laser by drilling billions of holes in a small bit of silicon using a nanoscale template."

    Finally, a laser to fit Dwarf Sharks!

    next up, an army of Barbie fem-bots!

    --

    A feeling of having made the same mistake before: Deja Foobar
  2. ahh! by 42Penguins · · Score: 0, Redundant

    "Nothing for you to see here. Please move along."

    Obviously nothing to see, with my eyes being burned out by a shark with a frickin silicon laser!

  3. Do you hear that? by chriswaclawik · · Score: 5, Funny

    That's the sound of a thousand slashdotters trying to make a "shark with friggin laser beams" joke before I do.

    --
    A guy walks into a bar... well, I forgot the joke, but the punchline is that he's an alcoholic.
    1. Re:Do you hear that? by Frostalicious · · Score: 3, Funny

      That's the sound of a thousand slashdotters trying to make a "shark with friggin laser beams" joke before I do.

      The true geek would have made the "house full of popcorn" joke before either of us.

    2. Re:Do you hear that? by kfg · · Score: 1

      Well, at least one of 'em made it.

      Loser.

      KFG

    3. Re:Do you hear that? by TenLow · · Score: 1
      So is it too late to make the house full of popcorn joke and still be funny?

      Speaking of, I think I'm gonna go get some popcorn.

    4. Re:Do you hear that? by Belseth · · Score: 1
      That's the sound of a thousand slashdotters trying to make a "shark with friggin laser beams" joke before I do.

      Actually that's a shark with silicone laser breast implants thank you very much.

    5. Re:Do you hear that? by DigitalReality · · Score: 1

      Screw popcorn, I just want to go ice skating, or sledding in the hallways of my dorm.

    6. Re:Do you hear that? by ThJ · · Score: 1

      In Norway the computer chip stuff is known as "silisium" and the breast implant stuff as "silikon"... but is there actually a difference?

    7. Re:Do you hear that? by ozmanjusri · · Score: 1

      but is there actually a difference?

      Well, since you're posting on Slashdot, you probably know what a silicon chip feels like, and yes there is a difference...

      --
      "I've got more toys than Teruhisa Kitahara."
    8. Re:Do you hear that? by ThJ · · Score: 1

      Rephrasing the question to better adapt for uninformative trolls: What -is- the difference?

    9. Re:Do you hear that? by ozmanjusri · · Score: 1

      Rephrasing the answer to better adapt for humourless Norwgians:

      Silicon is an element with similar chemical attributes to carbon. It is frequently used for electronics. Google for Jack Kilby and Robert Noyce to learn more about the development of semiconductors.

      Silicone is the generic description for an entirely synthetic polymer containing silicon and oxygen. Its percieved biological inertness and textural similarity to flesh led it to be used as breast implants. Google for breast implants. You won't learn much, but there's likely to be lots of interesting pictures.

      --
      "I've got more toys than Teruhisa Kitahara."
    10. Re:Do you hear that? by Articuno · · Score: 1

      Like, for example,

      Imagine a Beowulf cluster of sharks with friggin' silicon-based laser beams !

      ?

      Or

      1. Take a shark
      2. Add silicon-based laser to it
      3. ...
      4. Profit

      ?

      --
      So Long and Thanks for All the Fish!
    11. Re:Do you hear that? by ThJ · · Score: 1

      Ah... The "e" makes the difference in English. I didn't know that. So they -do- have silicon in common... I've already read up on the development of semiconductors, I have electronics as a hobby. It merely confused me that the two substances (apparently) were a homonym in English, but I was wrong on that one. When wil iu Inglish piip'l lörn thät ph'netiks is tha wei tuu gou? ;)

    12. Re:Do you hear that? by ozmanjusri · · Score: 1

      When wil iu Inglish piip'l lörn thät ph'netiks is tha wei tuu gou? ;)

      Cuando más de nosotros aprenden una segunda lengua sensible

      --
      "I've got more toys than Teruhisa Kitahara."
    13. Re:Do you hear that? by Anonymous Coward · · Score: 0

      Man, that's exactly what came to mind when I read this. That and the phrase "It was hot and I was hungry." Real Genius still is a great geek film.

    14. Re:Do you hear that? by alva_edison · · Score: 1

      It's all about Scuba Diving with Beauticians in an indoor pool.

      --
      He effected a bored affect.
    15. Re:Do you hear that? by petermgreen · · Score: 1

      don't worry plenty of us english don't spot that little difference in spelling.

      --
      note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
    16. Re:Do you hear that? by smithmc · · Score: 1

        The true geek would have made the "house full of popcorn" joke before either of us.

      Frostalicious? This is Jesus, Frostalicious. Stop playing with yourself!

      --
      Downmodding is the refuge of the weak. Don't downmod, make a better argument!
    17. Re:Do you hear that? by Anonymous Coward · · Score: 0

      Student beauticians!!

  4. Full Text: Site kinda slow already. by Erik_the_Awful · · Score: 4, Informative

    Brown Team Creates 'Impossible' Silicon Laser
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    PROVIDENCE, R.I., Nov. 21 -- Silicon has made its way into everything from computers to cameras. But a silicon laser? Physically impossible -- until now. A Brown University research team led by Jimmy Xu has engineered the first directly pumped silicon laser by changing the structure of the silicon crystal through a novel nanoscale technique.

    Since the creation of the first working laser -- a ruby model made in 1960 -- scientists have fashioned these light sources from substances from neon to sapphire. Silicon, however, was not considered a candidate. Its structure would not allow for the proper line-up of electrons needed to get this semiconductor to emit light.

    Now a trio of Brown University researchers, led by engineering and physics professor Jimmy Xu, has made the impossible possible. The team has created the first directly pumped silicon laser. They did it by changing the atomic structure of silicon itself. This was accomplished by drilling billions of holes in a small bit of silicon using a nanoscale template. The result: weak but true laser light. Results are published in an advanced online edition of Nature Materials.

    The feat is an apt one for Xu, whose Laboratory of Emerging Technologies is also known as the "laboratory of impossible technologies."

    "There is fun in defying conventional wisdom," said Xu, "and this work definitely goes against conventional wisdom -- including my own."

    For now, though, the possible isn't practical. In order to make his silicon laser commercially viable, Xu said, it must be engineered to be more powerful and to operate at room temperature. (Right now, it works at 200 C below zero.) But a material with the electronic properties of silicon and the optic properties of a laser could be useful in both the electronics and communications industries by helping to make faster, more powerful computers or fiber optic networks.

    Xu said that when lasers were invented, they were considered a solution looking for a problem. Now lasers are used to power CD players and barcode scanners, and they can cut everything from slabs of steel to delicate eye tissue during corrective surgery.

    "A very new discovery in science eventually finds an application," Xu said. "t will just take years of work to develop the technology."

    Light emission from silicon was considered unattainable because of silicon's crystal structure, and electrons necessary for laser action are generated too far away from their "mates." Bridging the distance to make the atomic connection would require just the right "matchmaker" phonon arriving at precisely the right place and time.

    In the past, scientists have chemically altered silicon or smashed it into dust-like particles to generate light emission. But more light was naturally lost than created. So Xu and his team tried a new way to tackle the problem. They changed silicon's structure by removing atoms.

    This was accomplished by drilling holes in the material. To get the job done, the team created a template, or "mask," of anodized aluminum. About a millimeter square, the mask features billions of tiny holes, all uniformly sized and exactly ordered. Placed over a bit of silicon then bombarded with an ion beam, the mask served as a sort of stencil, punching out precise holes and removing atoms in the process. The silicon atoms then subtly rearranged themselves near the holes to allow for light emission.

    The new silicon was tested repeatedly over the course of a year to ensure it met the classical criteria of a laser, such as threshold behavior, optical gain, spectral line-width narrowing and self-collimated and focused light emission.

    1. Re:Full Text: Site kinda slow already. by greenguy · · Score: 1

      I didn't RTFA, or the posted text, but... wait, what was this about, again?

      --
      What if I do the same thing, and I do get different results?
  5. Nice... by CriminalNerd · · Score: 1

    ...but will it be worth it to drill billions of holes into silicon to make lasers? I don't think it will be cost efficient until there are advances made in nanotechnology.

    1. Re:Nice... by pookemon · · Score: 1

      Sure, given how they "drill" the holes.

      --
      dnuof eruc rof aixelsid
    2. Re:Nice... by Anonymous Coward · · Score: 0

      You obviously didn't RTFA...

    3. Re:Nice... by aminorex · · Score: 1

      No way am I going to stay on the job long enough to drill even one billion holes in a microscopic piece of silicon. But maybe they can get a phillipino to do it.

      --
      -I like my women like I like my tea: green-
    4. Re:Nice... by digitalchinky · · Score: 1

      The correct spelling is "Filipino", but don't worry, life over this side of the big blue lake gets better every day - soon the Philippines will be outsourcing to America for all their factory needs.

  6. Mace, Tazers, Tai-Bo... by Alvaradolol · · Score: 1, Funny

    Now silicone lazers, I never get a break.

    1. Re:Mace, Tazers, Tai-Bo... by w.timmeh · · Score: 1

      Actually, it's "laser", an acronym for Light Amplification by Stimulated Emission of Radiation.

    2. Re:Mace, Tazers, Tai-Bo... by B3ryllium · · Score: 2, Funny

      siliCON, not siliCONE.

      You've got teh boobies on the mind, mate. There's more to life.

    3. Re:Mace, Tazers, Tai-Bo... by TheTerrorized · · Score: 1

      I think that was the joke..

    4. Re:Mace, Tazers, Tai-Bo... by B3ryllium · · Score: 1

      I'm sorry, I couldn't here your comment over that loud wooshing noice ;-)

    5. Re:Mace, Tazers, Tai-Bo... by Anonymous Coward · · Score: 0

      really?

  7. Re:Anyone care to explain the significance of this by whathappenedtomonday · · Score: 3, Insightful
    FTFA: "A very new discovery in science eventually finds an application," Xu said.

    In other words, it's neat, but useless. So far.

    --
    I hope I didn't brain my damage.
  8. It's as if... by Abuzar · · Score: 0, Offtopic

    billions of voices suddenly cried out in terror and were suddenly silenced.

  9. Yes, but what about the laser by pookemon · · Score: 0, Redundant

    Great, they've produced a laser from silicon - but what use is it? Anyone have a link to any info on the properties of the laser? Is it a blue laser, Infra red, a plain ol' red laser that everyone has in their DVD/CD player (or pocket)?

    --
    dnuof eruc rof aixelsid
    1. Re:Yes, but what about the laser by slashname3 · · Score: 0, Offtopic

      Actually this will be used for silicon laser breast implants for sharks. So not only will they have lasers on their heads but also in their bossoms. Three shots for each shark.

      Of course the real danger will be when women start getting lasers implanted in their breasts. When they say no they will really mean NO!

      Naturally most /.'ers will never have to face this problem.

    2. Re:Yes, but what about the laser by afaik_ianal · · Score: 1

      From TFA: But a material with the electronic properties of silicon and the optic properties of a laser could be useful in both the electronics and communications industries by helping to make faster, more powerful computers or fiber optic networks.

    3. Re:Yes, but what about the laser by pookemon · · Score: 1

      They say that about every laser - especially solid state ones. But if the laser is of a wavelength that is already in use, and isn't any smaller/cheaper etc. than the existing hardware then it's pointless. The only information (as you've quoted) is the standard "this could be useful" statement. It doesn't mention anything specific. Sure it might be useful for these things - but is the wavelength/strength/size/cost any better than existing technology?

      --
      dnuof eruc rof aixelsid
    4. Re:Yes, but what about the laser by rco3 · · Score: 1

      Yes. Because the laser is made with SILICON. Coincidentally, that's the same stuff your CPU was made from. You could, then, in theory, fabricate a laser on the same die as the CPU... or fabricate hundreds or thousands of on-die lasers for communications between regions or between IC's. The advantage of using Si is that it's cheap and well-understood, and we're already making the chips out of those. You can't fabricate a GaAs laser on the die with the CPU, you have to bond two different dice together.

      So the advantage is that you could fabricate the laser on the same die as the CPU, and the wavelength isn't as important as the tight integration and reduction of processing complexity. Yes, that's important.

      --

      Ce n'est pas un vrai mouvement de robot!
    5. Re:Yes, but what about the laser by Celsius+233 · · Score: 1

      Sharks != Mammals
      Sharks == Fish

      --
      Denham's Dentrifice, Denham's Dentrifice, Denham's Dandy Dental Dentrifice, Denham's Dentrifice Dentrifice Dentrifice.
    6. Re:Yes, but what about the laser by slashname3 · · Score: 1

      That's why they need the implants. :)

    7. Re:Yes, but what about the laser by Anonymous Coward · · Score: 0

      "Naturally most /.'ers will never have to face this problem."

      Yes, /.er's are a dying race.

  10. After RTFA... by GeneralEmergency · · Score: 2, Funny



    Summary: Stupid Silicon Tricks candidate. No viable application.

    Must be nice to be a Mad Scientist(TM) like "Jimmy" Xu. Nice big lab with all those blinking lights, bendy glassware and stuff.

    --
    "A microprocessor... is a terrible thing to waste." --
    GeneralEmergency
    1. Re:After RTFA... by Hal-9001 · · Score: 1
      Summary: Stupid Silicon Tricks candidate. No viable application.
      Well, it's going to take a few clever silicon tricks to make optoelectronic devices out of silicon. The linked article alludes to silicon's indirect bandgap, which is why silicon is such a troublesome optoelectronic material. Progress in computing speed and communications bandwidth will stagnate until we either discover how to make optoelectronic devices out of silicon or we discover how to make logic gates out of InGaAsP or AlGaAs. Because all of the existing infrastructure for silicon, it would be preferrable to develop silicon as an optoelectronic material. Thus I consider this device to be a valuable first step towards a useful silicon laser.
      --
      "It take 9 months to bear a child, no matter how many women you assign to the job."
  11. I won't buy this lazer by Coldglow · · Score: 0

    But i would buy X-Ray Silicon glasses... To see SiliconCones!!!! ;)

  12. Which one is first? by TechyImmigrant · · Score: 5, Interesting

    Another first silicon laser? So who was really first?

    ----
    http://oemagazine.com/newscast/2004/102604_newscas t01.html

    Los Angeles, CA | 26 October 2004 -- Researchers at UCLA have demonstrated the first silicon laser, which could lead to more effective biochemical detection, secure communications, and defense against heat-seeking missiles.

    ----
    http://www.intel.com/technology/silicon/sp/

    First Continuous Silicon Laser

    In a paper published February 17, 2005 by the prestigious scientific journal Nature, Intel researchers disclosed the development of the first continuous wave all-silicon laser using a physical property called the Raman Effect. They built the experimental device using Intel's existing standard CMOS high-volume manufacturing processes. This is the third silicon photonics paper Intel has published in Nature since 2004, beginning with the modulator breakthrough (see the Learn More section).

    ----
    http://www.photonics.com/readart.asp?url=readartic le&artid=325&bhsh=1050&bhsw=1680&bhqs=1

    PROVIDENCE, R.I., Nov. 21 -- Silicon has made its way into everything from computers to cameras. But a silicon laser? Physically impossible -- until now. A Brown University research team led by Jimmy Xu has engineered the first directly pumped silicon laser by changing the structure of the silicon crystal through a novel nanoscale technique.

    --
    Evil people are out to get you.
    1. Re:Which one is first? by Anonymous Coward · · Score: 0

      The other lasers used a pre-existing source of laser light.

    2. Re:Which one is first? by Anonymous Coward · · Score: 2, Informative

      Both the UCLA and Intel lasers were Raman lasers. Note that Intel was careful to claim only the first "continuous" all silicon raman laser so both are technically "first" reports. The excited state in this laser is a defect state related to an electron trapping vacancy and so the authors can claim another first. Unfortunately the trap is fairly shallow, so room temperature operation is probably not going to be possible.

      Note that all of these lasers require optical pumping by another laser and so have no real commercial value. The real prize will be an electrically pumped Si laser. (Although this may not be possible because electrical contacts lead to additional absorption losses, making the problem that much tougher.)

    3. Re:Which one is first? by Hal-9001 · · Score: 5, Informative
      • The UCLA laser was a Raman laser that could only operate in pulsed mode. The Raman effect is a nonlinear effect that requires several external laser beams to power the silicon device.
      • The Intel laser was also a Raman laser and was the first silicon Raman laser that could operate in continuous-wave (non-pulsed) mode.
      • The Brown laser is not a Raman laser. Therefore it only requires a single external laser beam to power the device.

      The holy grail, of course, is an electrically-pumped silicon laser where you apply a voltage directly across the device and get laser light out. We're not there yet, but each of these devices represents progress toward that goal. In particular, a device with direct optical pumping like the Brown laser suggests that direct electrical pumping might not be far off.
      --
      "It take 9 months to bear a child, no matter how many women you assign to the job."
    4. Re:Which one is first? by Ruie · · Score: 1
      Stupid question - but what is a laser diode ? Granted it is doped silicon, but why should we care ?

    5. Re:Which one is first? by archgoon · · Score: 1

      MMmmmh... Ramen Laser... beef flavored...

    6. Re:Which one is first? by Anonymous Coward · · Score: 0

      For some reason I just got a craving for noodles...

    7. Re:Which one is first? by Hal-9001 · · Score: 2, Informative
      Stupid question - but what is a laser diode ? Granted it is doped silicon, but why should we care ?
      Actually, most laser diodes are made of aluminum gallium arsenide (AlGaAs) or indium gallium arsenide phospide (InGaAsP). At the moment, there are no commercial silicon laser diodes because there are no silicon laser diodes. The reason, as is alluded to in the linked article, is that silicon is an indirect bandgap material, so a photon (a quantum of light or electromagnetic vibration) emission event can only occur if a phonon (a quantum of lattice vibration in the material--in this case, silicon) either arrives or leaves the location of the photon emission event at the same time. The probability of these events occuring simultaneously is vanishingly small, which makes optical processes in silicon extremely inefficient and makes it extremely difficult to use silicon as an optoelectronic material.
      --
      "It take 9 months to bear a child, no matter how many women you assign to the job."
    8. Re:Which one is first? by Anonymous Coward · · Score: 0

      Is that you, Naruto?

    9. Re:Which one is first? by petermgreen · · Score: 1

      diodes don't have to be made out of silicon!!

      diodes constructed in different ways out of different semiconductors can have very different properties

      --
      note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
    10. Re:Which one is first? by Busy · · Score: 1

      It's debatable whether the Raman effect is *real* science or not, but in addition to lasers, it can also be used to make mountains, trees, and midgets.

      --
      Think of someone with average intelligence. Now think 1/2 the world is dumber than that guy.
  13. So many impossible things done! by Datamonstar · · Score: 4, Funny

    First bubbles, now Lasers! Frikin' Lasers!

    --
    The eternal struggle of good vs. evil begins within one's self.
  14. Next up... by Anonymous Coward · · Score: 1, Funny

    glowing laser boobies!

    1. Re:Next up... by cyber-dragon.net · · Score: 1

      But will they be glowing silicon lazer boobies that make colored bubbles?

  15. What about diode lasers? by dsci · · Score: 4, Informative

    But a silicon laser? Physically impossible

    Diode lasers use silicon, or at least compounds of silicon. Some details here and here.

    Pretty cool, though that this is the "the first directly pumped silicon laser."

    --
    Computational Chemistry products and services.
    1. Re:What about diode lasers? by Soft · · Score: 1
      Diode lasers use silicon, or at least compounds of silicon.

      Actually, the first article you cite only mentions silicon carbide as a substrate, that is, what to grow the active material on (gallium nitride in this case); silicon is not involved in the laser emission. The second article is a bit misleading, in that it mentions silicon to illustrate what a semiconductor is, without insisting on the fact that silicon is not a good light emitter due to its indirect bandgap.

      At least, that is, under normal conditions; the original article authors' idea is to use a holey silicon device, where the band structure is presumably altered.

    2. Re:What about diode lasers? by cow-orker · · Score: 2, Informative

      Diode lasers use silicon, or at least compounds of silicon.

      They don't, unless you are willing to call the laser diode in your CD player a "plastic laser" because it's mounting in a plastic casing. The semiconductor in light emitting diodes is usually GaAs and never silicon, mainly because silicon diodes just won't emit light (no even infrared).

  16. Intel? by Anonymous Coward · · Score: 0

    I thought Intel made the first laser on silicon.

    link

    But what do I know? Maybe it's a different kind of laser.

  17. Intel already did this by warrior · · Score: 2, Interesting

    And they did it using ordinary semiconductor manufacturing methods. It was in spectrum a couple months ago, you can find it here: http://www.spectrum.ieee.org/print/1915 They're planning it for use in single-chip optical networking solutions.

    --
    Intel transfer the difficult from Hadware to software, for get more power, programmer need more technology. -- chinaitn
  18. so... by know1 · · Score: 0

    they finally frikkin did it. watch out for ill-tempered sea bass you insensitive cl...oh nevermind

  19. For their next trick... by tktk · · Score: 0, Troll
    they should start working on a silicone laser.

    You know...to make bigger boobies.

    1. Re:For their next trick... by Eric604 · · Score: 3, Funny
      they should start working on a silicone laser.
      You know...to make bigger boobies.

      That would be a silicone pump laser.

  20. confused by minus_273 · · Score: 1

    I'm confused. Do we mean this laser

    or thislaser?

    --
    The war with islam is a war on the beast
    The war on terror is a war for peace
  21. First things first... by Gojira+Shipi-Taro · · Score: 0, Offtopic

    How many of these can dance on the head of a shark?

    --
    "Oh my God. This is terrible. This is the end of my Presidency. I'm fucked."; ~ Donald J. Trump
  22. Unfortunately... by Anonymous Coward · · Score: 4, Funny

    From TFA...
    "Right now, it works at 200 C below zero."

    It looks like we'll be seeing penguins with laser beams long before sharks with lasers beams.

    1. Re:Unfortunately... by Jugalator · · Score: 1

      "Unfortunately"??

      Only a Microsoft ally would claim that armed laser-using penguin overlords were bad news!

      --
      Beware: In C++, your friends can see your privates!
  23. Porous Silicon by karvind · · Score: 2, Interesting

    Is this too much different from photoluminesence from porous silicon ? That was shown in 90s and yes it wasn't coherent.

    1. Re:Porous Silicon by Steve525 · · Score: 1

      Yes, it is different, and no it may not be. The difference is, as they state in the article:

      The new silicon was tested repeatedly over the course of a year to ensure it met the classical criteria of a laser, such as threshold behavior, optical gain, spectral line-width narrowing and self-collimated and focused light emission.

      These are characteristics for stimulated (the "s" in laser) emission, not spontenous emission, which is what you had in the previous photoluminesence work.

      However, it may not actually be caused by a different phenomenon then in porous silicon. It simply may just be more efficient in this geometry. It's a result that's not well understood at the moment.

  24. He was my prof at University of Toronto and by Anonymous Coward · · Score: 0

    even back then he was talking about defying conventions, doing the impossible, and thinking vertically, not horizontally... something like that.

    This must have been like 1993, in my engineering courses at U of T, and he was teaching us Quantum Physics in 2nd year. He was a challenging professor, he seemed extremely intelligent and more importantly motivated and ambitious, and I'm glad to see that he continues to do what other people deem impossible.

  25. just remember, boys, by Tumbleweed · · Score: 1

    "Always keep your optics clean."

  26. nanoscale template metaprogramming by smittyoneeach · · Score: 3, Funny

    smoke pouring soon out of a C++ compiler near you!

    --
    Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
  27. I don't know... by gargletheape · · Score: 0

    It seems like calling it a silicon laser is a bit iffy when you're drilling billions of holes all over it. I mean, those holes aren't silicon. In the limit you have no silicon at all, just a very big hole, with air in it ;)

  28. What about laser diodes? by apchar · · Score: 1

    Whats the difference between this and the laser diode found in any CD player or laser pointer?? Laser diodes have been around for 30 years.

    --
    ---Democracy is two wolves and a lamb voting on what to have for lunch.Liberty is a well armed lamb contesting the vote.
    1. Re:What about laser diodes? by serbanp · · Score: 4, Informative

      The laser diode you're talking about is not made of silicon...

    2. Re:What about laser diodes? by rco3 · · Score: 1

      What's different about it is that it's made out of the exact same stuff that your CPU is made of. So you could make a CPU with lasers on the die , reducing complexity and increasing compactness and integration. It's not that they're better lasers, it's that it opens the door to do more stuff with optical computing, networking, etc, ON CHIP. It's a real PITA to try to, e.g., combine GaAs lasers with a Si IC.

      Will it make it possible for your computer to have sex with you tomorrow? No. But it's important nonetheless.

      --

      Ce n'est pas un vrai mouvement de robot!
    3. Re:What about laser diodes? by aminorex · · Score: 2, Funny

      > Will it make it possible for your computer to have sex with you tomorrow? No. But it's important nonetheless.

      Didnt you just contradict yourself?

      --
      -I like my women like I like my tea: green-
    4. Re:What about laser diodes? by Anonymous Coward · · Score: 0

      We've had laser diodes for a fair while, but these tend to use compound semiconductors to get the bandgap to be direct. Silicon has an indirect bandgap and hence is bloody hard to get proper lasing, you get phonon emission which is not what you're aiming for. Porous silicon has the nice effect of making a more direct bandgap so you can get rid of the lattice vibration and just get photon emission from the recombination. It'll be interesting to see them finally get this working because we could see on-chip optical communication to get rid of clock skew.

  29. reference by Anonymous Coward · · Score: 0

    I don't see the article in Nature Materials. Can anyone else find the full reference?

  30. and the first thing it wrote into some rock..... by Anonymous Coward · · Score: 0

    NO KILL I

  31. Re:Anyone care to explain the significance of this by Ungrounded+Lightning · · Score: 5, Informative

    Currently, putting a practical laser on a chip means using a semiconductor other than silicon, such as gallium arsenide. But silicon has better properties for making large complex circuits - and the technology of doing so is more advanced on silicon than on other semiconductor materials.

    This means that when you want to hook up a laser to a logic circuit you end up with two separate chips and interconnections between them (or maybe with a separate layer of the lasing semiconductor grown onto a silicon chip.) This is a major hassle and expensive. It also costs a surprising amount of power to drive high-speed signals through the connection between the two chips.

    If it were possible to build the lasers on, and out of, the silicon chip itself it would drastically decrease the cost and power consumption of the resulting devices.

    Beyond this, it would be an enabling technology: It costs even more power to push signals between one silicon chip and another across a board or backplane. It would be nice to use a laser and optic fiber to make the connection. But why bother if you still have to spend the power to get the signal through the wiring from the silicon to a separate laser that generates the light? If you could put the laser on the silicon chip and save the power you could replace (at least) the critical high-speed wiring between chips with fibers, drastically increasing speed and cutting power.

    Up to now it hasn't been possible to get silicon to lase directly (although there has been some recent work with nanoscale laser structures grown on its surface.) Now they've found a way to do it.

    It isn't ready for prime time yet, by a long shot. But it's the initial crack in the wall, and breaking down this wall is a BIG DEAL. So researchers will be jumping on this. You might see additional breakthroughs and practical applications in shorter order than with other new technology breakthroughs.

    If they get it working efficiently in the region between room temperature and near boiling point where silicon chips normally operate you'll get another increment in processor speed/power/size tradeoffs.

    It's a way to sidestep yet another of the long string of roadblocks that have threatened to knock us off the Moore's Law curve.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  32. nanopourous silicon by platinumflame · · Score: 2, Interesting

    I'm not 100% on this, but I do believe this stuff has been out for a while. In the lab I worked in last summer, we experimented with trying to grow gallium arsenide nano wires on a silicon nanoporous sub strait. This stuff costs us about $100 US for a sliver the size of a nickel. The idea was that we hoped we could get the nano wires to grow strait up and down much more easy than conventional techniques. The experiment failed because the silicon substrait could not be cleaved easily and the temperatures needed to grow the wires was too far too high for the substrait (~950 C), even though the manufacturer claimed it would hold its form past that mark.

    1. Re:nanopourous silicon by Anonymous Coward · · Score: 0

      What kind of freak can spell Gallium Arsenide but not
      "Substrate and Straight" properly?

    2. Re:nanopourous silicon by Anonymous Coward · · Score: 0

      Thanks for saving me from saying it. "sub strait" LOL.

  33. Old Lasers? by Doc+Ruby · · Score: 1

    What do they make laser diode chips out of, like the ones in CD players and fiberoptic "lights"?

    --

    --
    make install -not war

    1. Re:Old Lasers? by iggymanz · · Score: 1

      usually gallium arsenide or sometimes gallium nitride.

    2. Re:Old Lasers? by kimvette · · Score: 4, Informative

      When did GaAs or GaAn become equivalent to Si?

      From http://www.mtmi.vu.lt/pfk/funkc_dariniai/diod/led. htm

      he radiative recombination of electron-hole pairs can be used for the generation of electromagnetic radiation by the electric current in a p-n junction. This effect is called electroluminescence. In a forward-biased p-n junction fabricated from a direct band gap material, such as GaAs or GaN, the recombination of the electron-hole pairs injected into the depletion region causes the emission of electromagnetic radiation. Such a device is called a Light Emitting Diode (LED). If mirrors are provided (usually by cleaved crystallographic surfaces of the semiconductor) and the concentration of the electron hole pairs (called the injection level) exceeds some critical value, this device may function as a semiconductor laser that emits a coherent electromagnetic radiation with all photons in phase with each other. LEDs fabricated from different semiconductors cover a broad range of wavelengths, from infrared to ultraviolet.

      The electrical conductivity of a semiconductor can be increased by adding doping elements, or small percentages of impurity elements, to the semiconductor. The presence of the small traces of impurity elements can yield extra charge carriers which are free to move through the material.

      In the compound gallium arsenide, each gallium atom has three electrons in its outermost shell of electrons and each arsenic atom has five. This gives an average of four electrons per atom in the compound. When a trace of an impurity element with two outer electrons, such as zinc, is added to the crystal, the result is the shortage of one electron from one of the pairs. This shortage sets up an imbalance in which there is a place in the crystal for an electron but there is no electron available. This is commonly called a "hole." This forms the so-called p-type semiconductor in which the conduction of electricity is by motion of the hole from one atom to another.

      --
      The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
  34. Highlights by TubeSteak · · Score: 2, Interesting
    Right now, it works at 200 C below zero.
    and
    The new silicon was tested repeatedly over the course of a year to ensure it met the classical criteria of a laser, such as threshold behavior, optical gain, spectral line-width narrowing and self-collimated and focused light emission.

    This is pretty cool stuff & its not something that they just figured out how to do.

    /I'd really like to know how they plan to go from -200C to room temperature.

    --
    [Fuck Beta]
    o0t!
    1. Re:Highlights by Plaid+Phantom · · Score: 1

      /well, when they figure that out, they'll let you know.

      --
      All comments are properties and trademarks of the voices in my head. Not like I'm gonna claim them.
  35. hahahaha by TubeSteak · · Score: 1

    Kent: My condolences on your meltdown.
    Chris Knight: What meltdown, Kent?
    Kent: I'm not saying you had one, because how would I know? But just in case you do.
    Chris Knight: You slime!
    Kent: It's your own fault, Knight. Didn't anyone tell you to make sure your optics are clean?

    http://imdb.com/title/tt0089886/
    "When he gets mad, he doesn't get even... he gets creative"

    Mitch: And from now on, stop playing with yourself.
    Kent: It is God.

    --
    [Fuck Beta]
    o0t!
  36. best quote by Tumbleweed · · Score: 1

    "Revenge ... it's a moral imperative."

  37. Re:Anyone care to explain the significance of this by IronChef · · Score: 1

    This means that when you want to hook up a laser to a logic circuit you end up with two separate chips and interconnections between them (or maybe with a separate layer of the lasing semiconductor grown onto a silicon chip.) This is a major hassle and expensive.

    And obviously, the less chips and interconnections you have the easier it is to ruggedize the product for extreme conditions... such as those found in a corrosive salt water tank full of sharks with lasers affixed to their frikkin' heads.

  38. Re:Brown: not just for rinsing out your GPA anymor by Anonymous Coward · · Score: 0

    wish you could get into brown...

  39. In Soviet Russia... by Urusai · · Score: 2, Funny

    ...only old people ask for sharks with friggin' laser beams on their heads.

    D'oh!

    I for one welcome our new silicon-laser-beamed-shark overlords, and would like to remind them that as a Slashdot poster I can provide valuable commentary to assist in rounding up citizens for your underground sugar mines. Or whatever. Alcohol is my friend...

  40. Si Laser? by SHUT_TEH_FACE · · Score: 3, Interesting

    This is particularly interesting to me. Not twenty minutes ago, my professor in Laser Theory spent a few minutes describing why Si lasers would never work, and we'd be rich to figure out how to get one to work.

    1. Re:Si Laser? by Anonymous Coward · · Score: 0

      Is you prof the dickhead who taught Laser Theory at San Jose City College?

      I can just see him making such a stupid statement.

    2. Re:Si Laser? by ColaMan · · Score: 1

      Does he read slashdot? Force him into a bet now! Provoke him a bit first, it'll make him bet something outlandish :-)

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
  41. xu? by Anonymous Coward · · Score: 1, Funny

    Xu said. "t will just take years of work to develop the technology."

            Funny, wouldn't have guessed Xu to be a Brit.

    1. Re:xu? by Linker3000 · · Score: 1

      If Xu was a Brit, he would have said: "We'll work on this for a couple of years, fail to make anything viable, sell the rights to a Far Eastern company for peanuts and watch them make it a commercial success and earn bazillions from it."

      --
      AT&ROFLMAO
  42. "I want 5 Megawatts by Mid-May!" by Anonymous Coward · · Score: 0

    Prof. Jerry Hathaway

  43. direct link to pdf of article by Anonymous Coward · · Score: 0
  44. Did you read the article? This isn't praticle. by MrJerryNormandinSir · · Score: 1

    I guess the Brown research team just wnated to see if they can emit laser light through silica. but man... it's not
    practicle, and it's very ineffecient. Why not focus research on creating something that's extremely effecient?

    1. Re:Did you read the article? This isn't praticle. by jpop32 · · Score: 1

      Why not focus research on creating something that's extremely effecient?

      Well, because things usually get extremely efficient only _after_ you focus your research on them.

  45. Re:Brown: not just for rinsing out your GPA anymor by MrJerryNormandinSir · · Score: 1

    We all know, if you don't have the grades to make it into Harverd, well, there is always Brown! hah!

  46. Power measurement by zaphod123 · · Score: 1

    The first silicon laser produced is not very powerful. It is an "A" cup. In three years the Dolly Parton laser should be in full effect.

    --
    :q!
  47. Re:Brown: not just for rinsing out your GPA anymor by otis+wildflower · · Score: 1

    Heh, had the grades, but I was too white and too middle-class to afford it..

    Like I said, if only public, affordable universities had such low grading standards!

  48. Laser, or waveguide? by Anonymous Coward · · Score: 0

    just out of curiosity... if I were to etch a bunch of - say - 630nm holes in a sheet of aluminum foil (a late nite playing with the SEM, and (probably) burning out a filiment), and shined a laser pointer at/through it, would that mean that I had invented an aluminum laser?

    what about a glass fiber? is that a glass laser, or just a fiber-optic wave guide?

    1. Re:Laser, or waveguide? by Hal-9001 · · Score: 1

      The difference between what you describe and what the research group at Brown did is that, in your case, you get the same 630 nm light out. The Brown group used 514 nm light (probably from an argon laser) to drive the device and observed a luminescence signal with a center wavelength around 1278 nm, which is what one would expect for silicon.

      I think your point is that the article is lacking details as to why the silicon needs to be nanopatterned in the first place, and even the preprint in Nature Materials fails to provide motivation for the nanopatterning. I suspect the nanopatterning either modifies the electronic bandgap in silicon (possibly making the nanopatterned silicon a direct bandgap material), or it creates a photonic bandgap that suppresses spontaneous emission or enhances stimulated emission, but that's just speculation on my part.

      --
      "It take 9 months to bear a child, no matter how many women you assign to the job."
  49. Moore's Law by Anonymous Coward · · Score: 0

    ...says nothing about processor speed, only the number of transistors. With shrinking fabrication processes and multi-core technology, I don't think we're at any risk of having no use for those extra transistors.

    1. Re:Moore's Law by Ungrounded+Lightning · · Score: 1

      The need for data to feed the chip requires external signals, and at multi-Gbps speeds that means big transistors with much more heat dissipation than the little ones shoving signals around the chip. Heat dissipation in a practical package is one of the limits on chip size. So the need for these drivers is one of the limits to how many transistors can go on a chip. Replacing them with lower-heat lasers would allow you to have more of the little ones, and more total. Thus is another roadblock to following Moore's Law (the true formulation) pushed back.

      There are also several other exponential formulations that get lumped with Moore's Law (even if they're not the original and official formulation). One of them is a similar doubling time for price-performance.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way