Yes. I am referring exactly that. A stream of electrons that is one
electron thick.
An electric current is generally NOT a "stream of electrons"
as you seem to be envisioning it. A conductor, obviously,
could not be "one electron thick" since conductors are not
made of free electrons, but rather atoms. Your next question,
no doubt, will be whether or not you can create a one-atom-thick
conductor, and I will leave that to you.
Would it be possible to have an electron beam in which only
one electron at a time were emitted? In theory, I suppose so, but
then we'll run into other problems.
Now, is it possible to have an AC electric current that's 60 Hz, 5
volts, 0.01 amperes, and only 1-electron-thick?
Sorry, no AC electron beams, at least not without some pretty
odd cicrumstances that take this out of the realm of any practical
consideration. (Like it wasn't already.) "5 volts" of current is
meaningless.
If the conductor is copper? If its ionized air? If its a vacuum?
Vacuum is not a conductor in the conventional sense; if you
are talking about current "flow" through a vacuum, then you
ARE talking about what is in essence a one-electron-at-a-time
electron beam, and that's certainly possible, but so what?
In the case of copper and other materials which would be acting as
conventional conductors, the thickness of the conductor obviously
could not be smaller than an atom of the conductor in question,
and best of luck getting atoms to line up single file for any
significant distance to play "wire" for you. Single-atom points
of contact through which electrons might pass can certainly
be envisioned, but then, so what? What's with this "thickness"
nonsense, anyway?
If your real question is whether or not one can envision a
"current" that's the equivalent of one electron at a time
passing a given point - sure. But again, so what?
Bob M.