How does one isolate a single electron? For example, the double-slit experiment requires that a gun fire a single electron at the slits. How do you get just one electron?

Dehmelt et al, managed to isolate an electron back in 1973...here's a link that should help explain it.

 

http://www.washington.edu/research/pathbreakers/1973c.html

How does one isolate a single electron? For example, the double-slit experiment requires that a gun fire a single electron at the slits. How do you get just one electron?

 

the double slit experiment is done with a photon, no?

The version of the experiment I've heard involves electrons. But if Dehmelt et al. only figured out how to do it in 1973, that puts the first double-slit experiment using electrons after 1973. I thought this experiment was done in the early half of the 20th century.

 

Thanks for the link, snail, but it doesn't explain how they did it.

the double slit experiment is done with a photon, no?

 

IIRC, it's even been done with buckyballs

It can be done with many many things including as yourdad says buckyballs which I think are still the largest particle to archeve the double slit experiment.

 

The experiment can be conducted with a stream of particles which shows that these particles have wavelike properties. But if you use individual particles then it shows that the individual particle passes through both slits.

 

After a quick google I found:

 

http://physicsweb.org/articles/world/15/9/1

 

Enjoy.

The double-slit experiment doesn't require single electrons (or photons, neutrons, atoms or molecules), it's just that you will get the interference pattern if you fire the particles through the slits one at a time. You get the pattern much faster if you use more, but that doesn't confirm the self-interference.

 

Single photons are easier, since you can attenuate a beam in a pretty straightforward manner. For electrons you'd need a source that doesn't produce many electrons. Perhaps a radioactive source that beta-minus decays.

 

more info

http://physicsweb.org/articles/world/15/9/1