Hi, recent EE graduate, I'm working on a project for myself. I dealt with mostly controls, signals, and digital stuff, and not enough electromagnetics or RF so I am pretty clueless here. If I were to radiate the full electromagnetic spectrum from dc to visible light onto a copper cable, would it pick up all the frequencies or would it kill off the higher frequencies entirely? Mainly I am interested in a few Terahertz (infrared). I know I'm missing a lot of info here so sorry if sound ignorant but this wasn't my area of study and its hard to pick this stuff up on your own. I know there are such things as waveguides and something with the ground plane when you are at really high frequencies but all I have to work on is what I learned in my electromagnetic interference class. With skin effect, I calculated that at that frequency a 20 mil copper cable would have R per meter = 447 ohms L per meter = 2.4 pH They both get smaller as the thickness of the cable decreases I made a lumped circuit approximation (not sure if this is correct to do with a 1meter cable and 3 THz signal) where I put 1 of each in series on each side of a load resistor and do AC analysis in LTSpice, which gives me an LP filter with w_0 of roughly 10 THz. So it seems like a 1m cable like this cable would be able to pass a signal at the frequencies I am interested in, but this doesn't really seem feasible because its saying that a really thick copper cable could pass visible light. I know nothing about antennas so I don't know if it could pick up the signal either. Is it at all possible to pick up a THz signal with a copper wire with proper filtering and gain or am I wasting my time?