I second this Emilio Pisanty's point: the power supply you are
envisioning is a light source. Now the question that remains is: can
you propagate this light through a wire, just like you would do with a
regular low-frequency electric signal?
To get a hint of the answer, look at how people use wires to transport
high frequency signals, into the many MHz up to the multi-GHz range. A
single wire doesn't work, because it has a tendency to radiate all the
power you feed it into the air as free electromagnetic waves. The trick
is to use two wires carrying opposite currents. You can think of them
as one being the signal and the other being the return wire, but their
roles could be symmetric. If you keep them close enough, most of the
electromagnetic field will be confined between them, and you will be
able to transmit the power without too much loses. You can further
reduce the losses by twisting the wires together. At the highest
frequencies, you would get best results by putting one wire inside the
other which, shaped like a tube, functions like a shield. This is called
a coaxial cable, and some of them are good up to tens of GHz.
The think that is not so intuitive is that, while the metal wires carry
the current, the actual power is carried by the electromagnetic field
that propagates between the wires. So the main role of the metal wires
is thus to guide the electromagnetic waves and, for this reason, the
high-frequency cables are considered to be waveguides.
Could you adapt this waveguide technique to the propagation of light?
The answer is yes, some people have indeed built nanosized coaxial
cables for this very purpose.