Storing an Image with a Single Photon: Quantum Mechanics at Work

[DaveC426913]

These guys are storing whole images using a single photon!

http://www.sciencedaily.com/releases/2007/01/070119094254.htm

I didn't think too much of the article until I read how they're doing it. It is pretty much living, breathing proof of QM's basic, weirdest principle.

"To produce the UR image, Howell simply shone a beam of light through a stencil with the U and R etched out. Anyone who has made shadow puppets knows how this works, but Howell turned down the light so much that a single photon was all that passed through the stencil.

Quantum mechanics dictates some strange things at that scale, so that bit of light could be thought of as both a particle and a wave. As a wave, it passed through all parts of the stencil at once, carrying the "shadow" of the UR with it. "

 

[cesiumfrog]

How do they get so much info back out? Do they pass the single photon through a gain medium afterwards?

 

[Charonic]

That wouldn't make sense, since a gain medium can only amplify information, I don't think it can actually write info in...

Anyway, even though I read about the double slit experiment, I don't fully understand it, so I'll leave this to the experts :)

 

[Hans de Vries]

How do they get so much info back out? Do they pass the single photon through a gain medium afterwards?

The image is not retrieved from a single photon. The picture is made up of
many photons gathered by a scanning single photon detector.

The proof that the image information was available in the wave-function of
the photon comes from a separate high intensity beam experiment which
shows clearly visible interference.

The point they make is that they can slow down the propagation to 1/300th
of the speed of light while retaining both phase and amplitude information.
Here is a description of the experiment on the web page of the authors:http://www.science.rochester.edu/depts/physics/archives/physics_012207.html Regards, Hans