

Physicists Dream Up the Antilaser - m0th87
http://www.wired.com/wiredscience/2010/07/antilaser/

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Groxx
That's... pretty vague. If it's a "time-reversed laser", it's implying this is
a beam which can be projected which cancels out light it encounters:

> _“By just tinkering with the phases of the beams, magically it turns ‘black’
> in this narrow wavelength range,” says team member A. Douglas Stone, a
> physicist at Yale University. “It’s an amazing trick.”_

If it's a _material_ :

> _Instead of amplifying light into coherent pulses, as a laser does, an
> antilaser absorbs light beams zapped into it._

> _Stone and his colleagues thought up the antilaser while wondering what
> might happen if they replaced the material inside a laser that reflects
> photons — the “gain medium” — with a material that absorbs light. In the
> right configuration, the absorbing material sucks up most of the photons
> sent into it, while the remaining light waves cancel out by interfering with
> one another._

then it's... an electrically-operated optical switch? Why not just state that?

If it's an optical switch, it's pretty awesome, granted, but the article
doesn't seem to be implying that except in a very low-importance way (and
still ambiguous about beam / material). They even mention that, as it only
absorbs a specific frequency, it can't be used (efficiently) in solar
panels... which implies you can extract energy from the absorbed light?

WTF Wired, make more sense.

~~~
gvb
_Even though the antilaser absorbs perfectly, it does so only at specific
wavelengths of light..._

That would make it more than an optical switch, which switches broad
bandwidths of light on or off. This implies that it is a perfect "notch"
filter (absorbs only a specific frequency/wavelength) that can also be turned
on and off. Notch filters are very important in communications technology.
Being able to turn a perfect notch filter on and off is very interesting.

Modulation of light (lasers) is an obvious potential application, especially
if it can be done very rapidly - direct modulation of lasers is somewhat
tricky.
[http://www.molphys.leidenuniv.nl/~thooft/laserweb/download/l...](http://www.molphys.leidenuniv.nl/~thooft/laserweb/download/laser_modulation.htm)

...of course, they have to build one first.

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turbofail
Interesting note, one of the physicists mentioned in the article is Chong
Yidong, one of the co-maintainers of emacs.

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mojuba
One possible application would be, I think, detection of certain materials
provided that antilasers are cheap to build. In other words, cheaper
replacement for spectral analysis.

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Daniel_Newby
This sounds like nothing more than a tuned resonator, like a dichroic mirror
or a Fabry-Perot resonator.

