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EMW Eigenfrequency Complex Permittivity Error

Karen Grutter Certified Consultant

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I am doing an eigenfrequency simulation that includes a material with complex, frequency-dependent permittivity. I defined the real and imaginary parts of the relative permittivity as global functions as follows:

myepsrR(x) = 3.9-(wp^2/(x^2+Gamma^2))
myepsrI(x) = Gamma*wp^2/(x^3+x*Gamma^2)

Then, under the basic material parameters definition, I added to the model input "Frequency (freq)". Having done that, I defined the relative permittivity as follows:

myepsrR(freq*2*pi)+j*myepsrI(freq*2*pi)

Under Wave Equation, Electric --> Model Inputs, I select: Frequency "From Solver"

When I try to compute the solution, I immediately get the following error message:

Division by zero.
- Function: /
Failed to evaluate expression.
- Expression: d(((-(wp^2)*Gamma)*(3*myepsrI__x__internalArgument^2+Gamma^2))/(myepsrI__x__internalArgument^2*(myepsrI__x__internalArgument^2+Gamma^2)^2),myepsrI__x__internalArgument)
Error in user-defined function.
- Function: ddmyepsrI_dmyepsrI__x__internalArgument_dmyepsrI__x__internalArgument

When I change the imaginary part of the relative permittivity to a constant, I do not get this error. This error appears for both the "relative permittivity" and "dielectric loss" settings under "Wave Equation, Electric" --> "Electric Displacement Field"


0 Replies Last Post 27 mag 2016, 13:45 GMT-4
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