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.

Comments

WRONG

[Khyber]

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?

Not white

[Anonymous Coward]

So it's not white, it's tri-colour.

Summary is inaccurate

[Geoffrey.landis]

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.")

Re:Summary is inaccurate

[Khyber]

Not necessarily. While these emitters are tunable, I doubt the red is getting down to 700nm, or the blue going into the 400-410nm violet range. Most RGB emitters, even tunable are peak 630nm red and 450-460nm blue. So this wouldn't cover the entire visible colorspace very accurately when it came to deeper reds and violets.