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Laser-Induced Damage in Optical Materials
Y, the surface admittance, is a very important parameter in its own right. At any
interface, it is the ratio of the total tangential magnetic and electric elds. It can be
thought of as a surface property, and not just of any real surface but also of any plane,
even one in the middle of a thin lm. We shall make use of it later in this chapter.
Reectance can now be dened in terms of ρ as
R
ρρ ρ
2
(13.10)
However, there is a caveat. If our incident medium suers from absorption, a curious
coupling between the irradiances of the incident and reected waves occurs through
what is known as the mixed ...