# How to calculate complex permittivity from complex conductivity

1. Aug 3, 2014

### carbon9

Hi,

I got the complex conductivity vs. frequency table of a metamaterial. Its first lines are like this:

f conductivity
1GHz 0.004+0.00297i
1.1GHz 0.004+0.00295i
1.2GHz 0.003+0.00294i

the table goes up to 10GHz.

Now the problem is that I need to enter this material into electromagnetic simulation tools. But these tools require a real permittivity and frequency dependent loss tangent (CST and HFSS). So how can I calculate complex permittivity (real permittivity and loss tangent) from the above data?

2. Aug 12, 2014

### Greg Bernhardt

I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?

3. Aug 12, 2014

### Staff: Mentor

I'm no expert in the field, but conductivity and permittivity would seem to be fairly orthogonal properties. Have you tried finding a table of permittivity for this material?

http://en.wikipedia.org/wiki/Electrical_conductivity

http://en.wikipedia.org/wiki/Permittivity

.

4. Aug 13, 2014

### DrDu

The problem is that there are many different conventions out there, but I would guess that in your case $\epsilon =\epsilon_0+\frac{i}{\omega} \sigma$.

5. Dec 4, 2015