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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."
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
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.
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.
...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.
Now silicone lazers, I never get a break.
In other words, it's neat, but useless. So far.
I hope I didn't brain my damage.
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
Another first silicon laser? So who was really first?
s t01.html
c le&artid=325&bhsh=1050&bhsw=1680&bhqs=1
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http://oemagazine.com/newscast/2004/102604_newsca
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.
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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).
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http://www.photonics.com/readart.asp?url=readarti
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.
First bubbles, now Lasers! Frikin' Lasers!
The eternal struggle of good vs. evil begins within one's self.
glowing laser boobies!
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.
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
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
You know...to make bigger boobies.
That would be a silicone pump laser.
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.
Is this too much different from photoluminesence from porous silicon ? That was shown in 90s and yes it wasn't coherent.
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.
"Always keep your optics clean."
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
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.
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
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
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.
What do they make laser diode chips out of, like the ones in CD players and fiberoptic "lights"?
--
make install -not war
This is pretty cool stuff & its not something that they just figured out how to do.
[Fuck Beta]
o0t!
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/
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Kent: It is God.
[Fuck Beta]
o0t!
"Revenge ... it's a moral imperative."
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.
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!
...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...
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.
Xu said. "t will just take years of work to develop the technology."
Funny, wouldn't have guessed Xu to be a Brit.
Sharks != Mammals
Sharks == Fish
Denham's Dentrifice, Denham's Dentrifice, Denham's Dandy Dental Dentrifice, Denham's Dentrifice Dentrifice Dentrifice.
That's why they need the implants. :)
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?
We all know, if you don't have the grades to make it into Harverd, well, there is always Brown! hah!
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!
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!
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."
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