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Researchers Demonstrate the World's First White Lasers
An anonymous reader writes: Scientists and engineers at Arizona State University, in Tempe, have created the first lasers that can shine light over the full spectrum of visible colors. The device's inventors suggest the laser could find use in video displays, solid-state lighting, and a laser-based version of Wi-Fi. Although previous research has created red, blue, green and other lasers, each of these lasers usually only emitted one color of light. Creating a monolithic structure capable of emitting red, green, and blue all at once has proven difficult because it requires combining very different semiconductors. Growing such mismatched crystals right next to each other often results in fatal defects throughout each of these materials. But now scientists say they've overcome that problem. The heart of the new device is a sheet only nanometers thick made of a semiconducting alloy of zinc, cadmium, sulfur, and selenium. The sheet is divided into different segments. When excited with a pulse of light, the segments rich in cadmium and selenium gave off red light; those rich in cadmium and sulfur emitted green light; and those rich in zinc and sulfur glowed blue.
It wasn't nanotubes, or 3D printed, or made by Elon Musk??? WTH!?
How long before some asshole points this at a plane and kills everyone on board?
Real full spectrum 'white' light, or just equalized peaks in the spectrum for RGB?
Isn't the point of a laser that it's a single wavelength? Doesn't this fly in the face of that or am I missing something?
Now I'm waiting for the first black laser.
These lasers are oppressing other lasers! They need to check their privilege!
This is not the first WLL. Those have been available for at least half a decade.
This is the first SOLID STATE WLL.
What's unique is that they figured out a way to grow three different crystals next to each other on the same substrate without having fatal flaws.
Holy fuck can the editors even be bothered to fact-check?
Oh, yea, what editors?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
So it's not white, it's tri-colour.
A racist laser, literally white power.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
The summary is inaccurate, or at least confusing. The summary says "lasers that can shine light over the full spectrum of visible colors", but the article says that this is three monochromatic spikes, red, green, blue, which together appear white. It also says that the choice of colors is tunable... but tunable lasers aren't new.
The summary also implies that it is "a" laser, but the article makes it clear that what they did is make three separate lasers on the same substrate (specifically "three parallel segments, each supporting laser action in one of three elementary colors.")
http://www.geoffreylandis.com
Someone get the sharks. This is as good as it gets.
Using a system of tubes in the fibre optic, they spread the spectrum of a red laser:
http://www.leica-microsystems.com/science-lab/white-light-laser/
So white (aka broad spectrum) lasers are not new.
With the lack of jobs for PhD's in academia (and elsewhere), ANY academic job gets tons of applicants. Only the best of the best get *any* job in academia nowadays.
You can pretty much count on anyone in the US who has a faculty job being one of the best of the best. Furthermore, this person is going to have access to plenty of cheap PhD labor.
Don't be surprised if you see pretty significant accomplishments coming from previously disregarded places.
White lasers are racist! We need Affirmative Action for Lasers!
If you've ever played with a normal monochrome laser in a dark room, you'll have seen how laser illumination makes things look speckly. Illuminating with this "white" laser will make superimposed speckly in three colours, with the locations of the speckles not coinciding, so it would be iridescent speckly.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
um, no, that shines 3 wavelengths of light.
in other related news, researchers tightly focus light bulb light. They contend that their invention should have a wide spectrum of uses, but critics argue that their results aren't coherent.
It was discussed since yesterday over on Reddit and the authors of the original paper even arrived to provide clarifications. That's how bad this article linked here is.
See the reddit discussion here:
https://www.reddit.com/r/scien...
Entia non sunt multiplicanda praeter necessitatem.
"What?!?! No! No one EVER made them like this!!"
uh huh
For albino sharks?
Isn't that some kind of Privilege?
Is Jesse Jackson going to get involved?
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Great White Lasers! Finally they're getting them on the sharks!
Proverbs 21:19
There is a big difference. It's not full spectrum.
It is a discrete laser that can emit three distinct wavelengths.
While this first proof of concept is important, significant obstacles remain to make such white lasers applicable for real-life lighting or display applications. One of crucial next steps is to achieve the similar white lasers under the drive of a battery. For the present demonstration, the researchers had to use a laser light to pump electrons to emit light. This experimental effort demonstrates the key first material requirement and will lay the groundwork for the eventual white lasers under electrical operation.
The thing they made is probably best thought of as nano-interleaved resonator cavity for a laser diode (which needs to have certain band gaps to emit the light). Apparently for this proof of concept, they actually had to excite this nano-structured cavity, with an actual laser. These nano-structures couples the energy to desired tunable optical wavelengths which are nano-interleaved and thus allows emission of "white" light from the laser diode structure.
As far as I can tell, the breakthrough is to manufacture these nano-structures (nano-wires or nano-sheets) on the same substrate near each other (nano-spaced). To do this they developed a ion-substitution process which allows them to build the nano-wire structure with one material with certain lattice constants and later replace atoms to create a different lattice constant (changing the resonant wavelength of the structure), This alllowed them to make "blue" which generally so different than "red" that it previously needed to be fabricated with a different structure (making it hard to make nano-structures next to each other).
Racist.
It's all about lasers, but no mentioning of ze sharks. Highly disappointing...