Learning Forum

[afshiin.a]

Hello.

In the Lumerical library section, in materials such as silicon and silicon oxide, when you check the real and imaginary part of permittivity at wavelengths such as 1360 nm, you can see that the imaginary part of permittivity is zero (according to the first photo). When I change the settings to refractive index, the value of the imaginary part of the refractive index becomes negative (-6.66*10^-16)!!!! (According to the second photo) Is this a software error? Why did this happen?

According to photonics principles, a material's refractive index is equal to the square of the permittivity material. How is it possible that when the imaginary part of alpha is zero, the imaginary part of the refractive index is equal to a negative number close to zero??

 

Please guide me

[Devika Padmakumar Nair]

 

Hello, 

Have you tried updating the software ?

You can download new version by going to Help–>Check updates

Please try not to post same question again or posting in another language. 

Thank you.