I observed the values of Zi for my sample is much lower (about 1 order of magnitude) than Zr? Please what is the physical interpretation of this result?
it is dependent on the working material also a real part of the impedance is due to the resistance (frequency independent component) developed and the imaginary part is due to the frequency-dependent component developed like capacitive or inductive components.
Zi is much lower than Zr indicates that the inductive (or capacitive) components of the device-under-test are negligible and the resistive components of the DUT are dominant.