Films minces à base de Si nanostructuré pour des cellules ...

Figure 5.12: The shapes of k(λ) and k (λ, x). Lorentzian t of the k(λ) obtained through
experiments, gives the shape of k(λ, x).
tel-00916300, version 1 - 10 Dec 2013
g(λ, x) dynamic = σ em(λ).N 3 (x).λ
4π
Eqn (5.34)
For a transition between i → j, the Lorentzian function for the emission cross
sections is represented as,
σ em. = σ em.max
1
1 +
(ω 2 ij(em.) −ω2 ) 2
ω 2 ∆ω 2 (em.)
Eqn (5.35)
where σ em.max is the maximum value of emission cross sections, ω ij(em.) is the
frequency of emission transitions and ∆ω is the width of the Lorentzian curve of
emission. Figure 5.13 shows the typical shapes of σ(λ) abs. and σ(λ) em.
5
Figure 5.13: Illustration of emission and absorption cross-sections for arbitrary inputs.
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