Loss tangent of Sio2 and Si at THz Frequency [193 THz] ?

Can anyone tell me the value for Loss tangent of Silicon dioxide (SiO2) and Silicon (Si) at 193.5 THz. I have read a lot of literature but the closest value I could find was 0.005 @ 10 THz...Not greater thn this..

Kindly reply.

Regards

Your asking about near IR wavelength.

I'm sure you'll find absorbance numbers in optical material data. Of course the structure matters. Crystalline SiO2 (fused silicia, quartz) has a good transparency around 1.5 μm, absorption of IR quality quartz fibre optic is measured in dB/km. Silicon has a low pass wavelength of about 1 μm and still some absorption at 1.5 μm. You should be able to calculate a loss tangent from optical data (after correction for reflection losses).

Thanks for the detail reply..If possible can you refer some papers as well..

And what about the Drude model? does it help for Substates or its just to get the n-k values for metals only?