Amplitude and energy relation in optics

AI Thread Summary
The discussion centers on the relationship between amplitude, energy, and transmission coefficients at the interface of two dielectric mediums. The user questions whether the transmitivity of power should be calculated as (n1/n2)²*t² instead of n2/n1*t², given that electromagnetic energy is related to the electric field squared. They reference the definition of the transmission coefficient as the ratio of transmitted intensity to total intensity, emphasizing that intensity correlates with electromagnetic energy. The conversation explores the implications of these relationships in optics. The inquiry seeks clarity on the correct formula for calculating power transmitivity in this context.
amir11
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Hi Guys

I have a very simple and basic question. Assume interface of two dielectric mediums. If the t is transmition cofficient for electricfield from medium 1 to medium 2 with refractive indexs n1 and n2, what is the transmitivity of power from medium 1 to medium 2?

I know it is n2/n1*t2. But wouldn't you expect it to be (n1/n2)2*t2 because the elecromagnetic energy is defined as epsilone*E2 which is the same as n2E2?
 
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From what I remember the transmition coefficient is defined as the ration of the intensity that is being transmitted to the total intensity and intensity is proportional to the electric field squared. Intensity is proportional to em energy. Does it make sense?

Cheers.Roman.
 
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