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

From the two cases shown in this gure, it can be noticed that the angle of
incidence inuences the intensity and position of the pump maxima. This indicates
that with 45° incidence used in our PL experiments, the pump intensity is lower
than that obtained in normal incidence.
(b) Inuence of thickness
tel-00916300, version 1 - 10 Dec 2013
The inuence of the lm thickness (d) on the pump prole was investigated for three
cases: d = 300 nm, 500 nm and 1000 nm (Fig. 5.4).
In all the three cases shown in
this gure, the angle of incidence
was xed at 45°, and the refractive
index is as described before (ref.
Fig. 5.2). It can be seen from gure
5.4 that only by varying the total
thickness there is a change in the
position and intensity of the pump
prole. This can be related to the
reection in the lm denoted as r glob
in equation 5.10, which is a function
of lm thickness. These results
Figure 5.4: Inuence of total lm thickness on
clearly indicate that the mean pump
the pump prole.
intensity varies non-monotonously
with thickness (Tab. 5.1).
Thickness (d) nm Pump intensity range W/m 2
300 1 x 10 4 - 8 x 10 4
500 2.5 x 10 4 - 1x10 5
1000 2 x 10 4 - 9.5 x10 4
Table 5.1: The pump intensity range for the three thicknesses investigated.
(c) Inuence of complex refractive index
The inuence of the real part and imaginary part of the complex refractive index
on the pump prole were investigated.
(c1) Real part (n 2 ):
To witness the contribution of n 2 on the pump wave that travels from medium
1 (air) to medium 2 (thin lm), simulations are made by considering three SRSO
monolayers with 500 nm thickness and three dierent refractive indices (n 2 = 1.48,
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