Interference of two independent electron beams?

[tris_d]

This is about "double slit" setup only without slits and instead there are two electron beams. I found some experiments doing something like this, but the setup was always rather complex, with some mirrors and such. So the question is why can't we get interference pattern by simply crossing two electron beams, or can we?

 

[mfb]

To get (visible) interference, you need a fixed phase between the electrons in both beams. Just random, uncorrelated electrons won't give interference.

 

[tris_d]

To get (visible) interference, you need a fixed phase between the electrons in both beams. Just random, uncorrelated electrons won't give interference.

Ok, but I couldn't find any such experiment that would simply cross two electron beams. Would that mean it is not possible to have two correlated yet independent electrons beams coming directly out of electron guns, or should I just google for it harder?

 

[mfb]

"Independent" implies "uncorrelated". No, it cannot be possible.

 

[AJ Bentley]

Electron diffraction is actually quite easy.

You don't need two beams. If you send a single beam through a crystalline material (metal foil) you get diffraction patterns.

http://en.wikipedia.org/wiki/Electron_diffraction#Electron_diffraction_in_a_TEM

All you need is an electron microscope.

 

[tris_d]

Electron diffraction is actually quite easy.

You don't need two beams. If you send a single beam through a crystalline material (metal foil) you get diffraction patterns.

http://en.wikipedia.org/wiki/Electron_diffraction#Electron_diffraction_in_a_TEM

All you need is an electron microscope.

Yes, that's what I could find. But then I wondered why not two independent beams.

 

[AJ Bentley]

No coherence.

Sadly, that makes it impossible to build a truly holographic imaging system for electron diffraction.
If it were possible, we could directly image the atomic structures (such as DNA) instead of having to infer them from the diffraction patterns with some guesses thrown in.

It's been a bit of a Holy Grail in Low Energy Electron Diffraction (LEED) for some time.