Hi Doctors & Great scholars,
After finding some of myths from electrical, electronic and optical properties of nanomaterials, now i am facing difficulty in electrical measurement. Is there any way or possibility to find find Epsilon/permittivity/Dielectric constant from Impedance values. Kindly, Help me.
Yes. This is called effective medium theory, homogenization, or parameter retrieval. Lecture 15 at the following link should have everything you need.
http://emlab.utep.edu/ee5390em21.htm
Dear All,
Thanks for your valuable contribution on my research. Really helpful.. !!
Z =Z' + iZ", It comes from J=dD/dt in which we assume no dc current. But, we will get a Z which has dielectric loss (ac) which acts as the "resistance" - like loss. This is where the Z comes from = a purely reactive impedance and a loss. Please follow this: epsilon = eps = eps' - i eps", D = eps E, E=Eo exp(iwt) where w = omega=2piF, f= frequency.
Now, J = dD/dt = eps dE/dt = (i w eps' + w eps" ) E, which when you write as I =J A, and E=V/d, for A= area and d = thickness, you end up with I = A/d (w eps" + i w eps')V. Notice that this is I = G(w) V, or V = I Z. Now you can see that due to "dielectric loss" you have an equivalent circuit of a real capacitor as a parallel circuit of a resistive impedance (due to w eps") and a true capacitance Z = 1/i w C. Work ou the V=IZ equation and you can easily see that Z' and Z" relate to a 1/Z = 1/Z' + 1/Z". But notice, that if you have dc leakage current then you separate the dielectric loss (frequency dependent) from Io =GoV, where Go = 1/Ro simply by noticing that Z" = tan(delta) Z' where delta is the phase angle between loss and C. And for dc Leakage you conduct an IV dc plot, which will then give you a total current Itotal = I(w) + Io. Good luck.
Saidi Hamza
sir alsiln note as mentioned is the permittivity of free space i.e. ε0 whose value is 8.854*10^(-12) Fm^(-1).
Hello Anil Arya, Please mention the text/reference from which you have shared the formulae for calculating permittivities from impedance spectra.
Thanks and Regards
Vishnu.
PLEASE, did you have any reference for the calculation.... paper or book
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