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Relative permittivity from text file

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Dear all,

I would like to use the relative permittivity fit for silver provided by the FDTD Solutions software by Lumerical. I exported this fit as two ASCII text files consisting of two columns separated by spaces. The first file contains the wavelength vs. real part of the relative permittivity, whereas the second file contains wavelength vs. imaginary part of the relative permittivity. My aim is to use the data as it is without any interpolation. There is only interpolation function which allows me to import this function and that is exactly why I posted this thread. How can I do so?

Thanks in advance

P.S: I am working with COMSOL 5.1 RF Module on Windows 7. I have also attached a relevant screenshot.


4 Replies Last Post 22.12.2015, 02:59 GMT-5
Sergei Yushanov Certified Consultant

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Posted: 9 years ago 08.12.2015, 08:57 GMT-5
Ongun,

Create interpolation function int1 using the first file containing the wavelength vs. real part of the relative permittivity. Create another interpolation function int2 using the second file containing the wavelength vs. imaginary part of the relative permittivity. Then, define relative permittivity as following:
eps_r=int1(c_const/lam)-j*int2(c_const/lam)

Regards,
Sergei
Ongun, Create interpolation function int1 using the first file containing the wavelength vs. real part of the relative permittivity. Create another interpolation function int2 using the second file containing the wavelength vs. imaginary part of the relative permittivity. Then, define relative permittivity as following: eps_r=int1(c_const/lam)-j*int2(c_const/lam) Regards, Sergei

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Posted: 9 years ago 08.12.2015, 11:14 GMT-5

Ongun,

Create interpolation function int1 using the first file containing the wavelength vs. real part of the relative permittivity. Create another interpolation function int2 using the second file containing the wavelength vs. imaginary part of the relative permittivity. Then, define relative permittivity as following:
eps_r=int1(c_const/lam)-j*int2(c_const/lam)

Regards,
Sergei


Dear Sergei Yushanov,

Thanks for the suggestion, I did as you instructed and it worked. However, I do not want Comsol to interpolate the data in any case. How can I achieve this behaviour(it can return an error when a wavelength not in the table is selected)? This is crucial as I want to have consistent results between Lumerical and Comsol.
[QUOTE] Ongun, Create interpolation function int1 using the first file containing the wavelength vs. real part of the relative permittivity. Create another interpolation function int2 using the second file containing the wavelength vs. imaginary part of the relative permittivity. Then, define relative permittivity as following: eps_r=int1(c_const/lam)-j*int2(c_const/lam) Regards, Sergei [/QUOTE] Dear Sergei Yushanov, Thanks for the suggestion, I did as you instructed and it worked. However, I do not want Comsol to interpolate the data in any case. How can I achieve this behaviour(it can return an error when a wavelength not in the table is selected)? This is crucial as I want to have consistent results between Lumerical and Comsol.

Maxim Electromobility

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Posted: 9 years ago 10.12.2015, 12:59 GMT-5
Hi Ongun,

Run your calculation only at those wavelengths, that are in your table. Than the refractive index will be exactly as in the table, and in Lumerical.

Best regards,
Maxim
Hi Ongun, Run your calculation only at those wavelengths, that are in your table. Than the refractive index will be exactly as in the table, and in Lumerical. Best regards, Maxim

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Posted: 9 years ago 22.12.2015, 02:59 GMT-5

Dear all,

I would like to use the relative permittivity fit for silver provided by the FDTD Solutions software by Lumerical. I exported this fit as two ASCII text files consisting of two columns separated by spaces. The first file contains the wavelength vs. real part of the relative permittivity, whereas the second file contains wavelength vs. imaginary part of the relative permittivity. My aim is to use the data as it is without any interpolation. There is only interpolation function which allows me to import this function and that is exactly why I posted this thread. How can I do so?

Thanks in advance

P.S: I am working with COMSOL 5.1 RF Module on Windows 7. I have also attached a relevant screenshot.


Hi Ongun :
I also want to import the relative permittivity for silver, but i don't know how the use the interpolation, can you send me your .mph file which use the interpolation so i can follow your step to import the relative permittivity for silver and use it. My e-mail address is :wangmiaoshou@126.com.

Thanks in advance!
[QUOTE] Dear all, I would like to use the relative permittivity fit for silver provided by the FDTD Solutions software by Lumerical. I exported this fit as two ASCII text files consisting of two columns separated by spaces. The first file contains the wavelength vs. real part of the relative permittivity, whereas the second file contains wavelength vs. imaginary part of the relative permittivity. My aim is to use the data as it is without any interpolation. There is only interpolation function which allows me to import this function and that is exactly why I posted this thread. How can I do so? Thanks in advance P.S: I am working with COMSOL 5.1 RF Module on Windows 7. I have also attached a relevant screenshot. [/QUOTE] Hi Ongun : I also want to import the relative permittivity for silver, but i don't know how the use the interpolation, can you send me your .mph file which use the interpolation so i can follow your step to import the relative permittivity for silver and use it. My e-mail address is :wangmiaoshou@126.com. Thanks in advance!

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