Diploma thesis

SHG Efficiency (a. u.)
1200
1000
800
600
400
200
Figure 4.37: Measurement setup to detect the pump intensity and SHG
intensity after the waveguide
SHG in the KTP waveguide Λ =104.17 mum, Pump Power = 15 µW
1400
0
1000 1100 1200 1300 1400 1500 1600 1700
λp [nm]
Figure 4.38: High power measurement
SHG efficiency (a. u.)
SHG in the KTP waveguide Λ = 104.17 mum, Pump Power = 8 µW
250
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50
0
1400 1450 1500 1550
λp [nm]
1600 1650 1700
Figure 4.39: Low power measurement
ond measurement with a higher pump power, at 1542 and 1628 nm (Figure 4.38).
The differences in the detected phasematching points can be because of several reasons.
Between the first measurement with the peak at 1525 nm and the following
experiments we changed the waveguide in the crystal. Manufacturing errors most
likely have shifted the phasematching point, between the first measurement and the
subsequent ones in another waveguide. The slight difference in the peak positions
in figure 4.38 and 4.39, is most likely due to simple measurement uncertainties.
We adjusted the error vector to this new data, presented in figure 4.38 and got
Table 4.4. In Figures 4.40 and 4.41 we plotted the new corrected functions.
The results of this investigation are a successful detection of two different phasematching
orders (m = ±1, in crystal ITI0706-B12). Furthermore around 1600 nm
we could detect two degeneracy points for the same contour. Consequently between
this two points a positive slope with exactly +45 ◦ degrees exists and we will be able
to produce decorrelated photon pairs with this crystal.
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