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Breakthrough In Plastic Lasers
esocid writes "Conventional electrically-powered laser diodes used in everyday consumer goods like DVD players are currently based on inorganic semiconductor materials such as gallium arsenide, gallium nitride, and related alloys. Plastic laser diodes offer the promise of covering more of the light spectrum than their counterparts, from near ultraviolet to the near infrared. Yet despite over a decade of research worldwide, plastic laser diodes have not yet been demonstrated because there haven't been any plastics that could sustain a large enough current while also supporting the efficient light emission needed to produce a laser beam. Now researchers at Imperial College London, publishing their findings in Nature Materials in April, are studying a plastic related to PFO (polydioctylfluorene), a blue-light emitting material; by making subtle changes in the plastic's chemical structure they have produced a material that transports charges 200 times better than before, while actually increasing its ability to emit light efficiently."
Now, all we need is a breakthrough with plastic sharks.
Knowledge is power. Knowledge shared is power lost.
How tunable would these emitters be? Are they suitable as general light emitting components, rather than "just" lasers? Would it be possible to create displays where the color of a pixel was actually changed in real time?
to post redundantly about sharks on slashdot!
sigs... don't talk to me about sigs....
Cool, the US government has worked out another piece of technology from the Roswell crash.
The original article is here here.
Something cool is that while traditional semiconductor lasers have an output wavelength that is very much controlled by the bandgap energy of the material, here the laser is substantially tunable by adjusting the plastic's thickness. (Of course, this is just adjusting the energy states too, but it seems more tunable.) From the paper, "Tuning the film thickness (45-160 nm) enabled access to lasing wavelengths across a 45 nm spectral window (434-479 nm)."
While it's not real-time electrical tuning over that kind of bandwidth, it's still pretty cool. Tunability is especially useful for detectors of various chemicals, and now this is getting into the wavelength range where more biological substances start to have their spectrographic signatures.
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Electronics kits for the digital generation!
This is moving in the right direction.
The holy grail is an electrically pumped organic laser. Varying the co-polymer ratios has improved electron mobilities, but they still have many orders of magnitudes to go before they would get into the likely energy densities required for lasing.
People are attacking it from multiple ends. Bradley's group have gone at it by taking an efficient light emitter and attempting to improve its pitiful charge mobilities. Others have taken very good charge carrying organic materials, LETs (light emitting transistors) and attempted to improve their pitiful light emission. (paper)
Did Vader just make the breakthrough he needed to construct the Death Star laser?
But was it invented by a teenager?
Now my LEGO Gun will be complete!
MWAHAHAHAH!
What is best in life? To crush your enemies, to see them driven before you and to hear the lamentations of their women.
Would they be called 'plasers'?
... with our plastic consuming bacteria!
You know, every bomb has an LED readout that counts down the minutes and seconds. I saw it on TV. Even nukes have them.
well?
http://en.wikipedia.org/wiki/Polydioctylfluorene
Please improve.
Shortly after earning my bachelors degree from an unnamed college in the Northest, one of my parent's friends took me aside at a party and gave me a recommendation for a successful career. His advice consisted of two words: plastic lasers.
I didn't listen to him then but I believe him now.
Also, I slept with his wife.
I think the way you choose to talk will repel people (or grown-ups, at least) just fine.
she was also plastic
Btw, gallium arsenide and gallium nitride are not alloys; they're inorganic compounds. An alloy is a mixture of two or more metals. There is a fundamental difference. /wisecrack
Looks like people nowadays aren't even mindful enough to put the comma in when writing about Imperial College, London.