Extracting the contribution of conduction in permittivity measurements using the Kramers-Kronig relations

The measurement of the material permittivity is often performed via an impedance measurement. In this case the measured permittivity includes the conduction contribution. Most of the time, the impedance-meters performing such measurement do not perform static measurement even if they can go to low frequencies. When the dipolar relaxation of the material leads to low frequency relaxation, separating the relaxation phenomenon from the conduction phenomenon can be difficult, especially when multiple relaxation phenomena superimpose. In this work we use the Kramers-Kronig relations to perform that separation by considering the frequency response aspect of the permittivity. The practical aspect of the method is presented and demonstrated on real measurements