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The following simulatino results were calculated with distances L1 = L2 = 25 mm between the reflection mirrors and the crystal. As only an approximation of the bounce geometry could be simulated, a deviation of up to 50% with the resulting output pwoer figures must be considered.
In diagram 5 the median average output power of the laser beam in CW mode is shown as a function of the absorbed pumping power. The reflecivity of the uncoupling mirror was set to R=0.9. The beam power approximately increases linearly to the absorbed pumping power up to 35W and then turn into an exponential function up to a pumping power of 51W, where the maximum output power of 24W is reached. Thus, a effiency of about 50% is achieved. Thomas and Damzen, 2011 reached an output power of 13.8W (with R=0.7) and efficiency of only 30%.
Diagram 6: Simulated median average output power of the laser beam as a function
of the absorbed pumping power; CW mode with R=0.9
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Additionally, a simulation with Q switch was performed (diagram 7). Here, too, a linear dependency of median outputpower average output power and absorbed pumping power can be observed, as in CW mode. This simulation resulted in an output power of 17W at a maximum pumping power of 51W. Compared to Thomas and Damzen, 2011, where an output power of 11W at R=0.7 was measured, this computed value is much higher. The cause of this is the lack of a real bounce geometry in the simulation. A lower output power needs to be expected in reality, therefore, as in CW mode.
Diagram 7: Simulated median average output power of the laser beam as a function
of the absorbed pumping power; with Q switch and R=0.9
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The simulation was also used to calculate the median average output power as a function of the reflecitity ouf the output mirror. Diagram 8 shows a power reduction with increasing reflectifity. Taking the results of Thomas and Damzen, 2011 in consideration, here we can expect a less intense reduction of the power in experimental test runs, too.
Abbildung 8: Simulated median average output power of the laser beam as a function
of the output mirror reflectivity with a pumping power of 51W
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