High frequency behaviour of copper

[debajyoti datta]

Will copper behave as a dielectric in high frequencies?...I tried to answer the question with loss tangent but relative permittivity of copper posed a problem...everyone on internet opines differently about relative permittivity of metals...then I looked at skin depth which decreases with frequency...but with appreciable high frequency also...skin depth is not zero...please through some light !

 

[davenn]

Will copper behave as a dielectric in high frequencies?...

what is your definition of high frequencies ?
copper still works well at least to 100 GHz

Dave

 

[Khashishi]

I think the answer is yes. Take a look at https://en.wikipedia.org/wiki/Plasma_oscillation
Metals can act like dielectrics above the plasma frequency, which is in the PHz range.

 

[debajyoti datta]

@Khashishi wikipedia link does not mention that it works as dielectric...@davenn i am talking about highest frequency used for communication purposes

 

[davenn]

i am talking about highest frequency used for communication purposes

tho there is stuff above 40 GHz ... 38GHz is pretty common for microwave links between cell towers etc

there's no problems using copper PCB tracks at these frequencies, waveguide is always used to get the signal to and from the antennas

most commercial stuff above 40 GHz is vehicular crash avoidance radar etc

 

[debajyoti datta]

thanks...and would you please say something about relative permittivity of metals ? ...or at least tell me some reliable sources to read.