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Author Topic: How do you control single photons?  (Read 1288 times)

Offline thedoc

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How do you control single photons?
« on: 18/07/2012 02:30:02 »
Jude Adamson asked the Naked Scientists:
   
In the Double Slit experiment, single photons were fired through a slit and caused an interference pattern. How did they create a device that would fire one photon at a time?

What do you think?
« Last Edit: 18/07/2012 02:30:02 by _system »


 

Offline Geezer

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Re: How do you control single photons?
« Reply #1 on: 18/07/2012 07:17:15 »
This is really one for JP, but let's see if I can remember what he told me.

You reduce the energy supplied to some sort of light source (I suppose a filament type light bulb will do) until it is only occasionally emitting a photon. You know it's only emitting photons occasionally by detecting them with a photoelectric cell. Each time one arrives at the cell, the cell will produce a pulse of electric current.
 

Offline syhprum

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Re: How do you control single photons?
« Reply #2 on: 18/07/2012 09:35:18 »
I think you have to interpose filters of varying "D" values untill you can detect photons popping out one at a time with your photo multiplier, the chief difficulty is getting the lab sufficiently dark
 

Offline yor_on

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Re: How do you control single photons?
« Reply #3 on: 18/07/2012 13:20:46 »
Download This pdf for an example. Then you have LED fires one photon at a time. and SINGLE-PHOTON LIGHT SOURCES: It’s hard to get just one photon. that's the new, simpler, way, as i understands it. I think you can use diamonds too, to get that kind of excitations, and as a added feature, ahem, a diamond is a girls best friend :)

Maybe?
 

Offline syhprum

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Re: How do you control single photons?
« Reply #4 on: 18/07/2012 14:10:37 »
I wonder if PMT,s can be damaged by excessive light when they are not plugged in or plugged into their normal resister chain but not powered.
I have handled PMT,s in both configurations with no apparent damage but would like another opinion 
 

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Re: How do you control single photons?
« Reply #4 on: 18/07/2012 14:10:37 »

 

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