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==Daily Log==
'''8/15/14'''
Deniz can calculate the maximum theoretical conversion efficiency of 780 if we know the amount of 1064 and 1555 in the cavity. I separated the beams with a prism and measured 5 mW maximum of 1064 when locking and 14 mW maximum of 1555. The prism (Thorlabs PS853) has a listed transmittance of ~28% for both 1064 and 1555, so exiting the cavity there should be 17.9 mW of 1064 and 50 mW of 1555.
Rechecking 1064 and 1555 power measurements since they don't seem right--1555 should be higher power than 1064. The bandpass filter lets through ~65% 1555 and blocks almost all 1064. I'm skeptical of the 28% transmission for the prism--check tomorrow.
 
The cavity mirror transmits 32 ppm and 38 ppm of 1064 and 1555 respectively, so that puts the powers at 559 W and 1316 W inside the cavity. The beam sizes were both about 1700 μm 30 cm from the cavity, so their intensities are approximately:
 
<math> 770 </math> <math> MW/cm^2 </math> and <math> 1810 </math> <math> MW/cm^2 </math>
 
I'm skeptical of the prism transmission figure, since I haven't observed losses like that. I'll check directly tomorrow when the cavity is aligned. The bandpass filter lets through ~65% 1555 and blocks almost all 1064.
 
 
 
'''8/4/14'''
New efficiency measurement is <math> 5.5*10^{-7} </math> In addition to walking the 780 beam, I also slightly adjusted its polarization and the focus of the a-sphere on the output fiber launch, both of which slightly improved efficiency.
 
 
Deniz can calculate the maximum theoretical conversion efficiency of 780 if we know the amount of 1064 and 1555 in the cavity. I separated the beams with a prism and measured 5 mW maximum of 1064 when locking and 14 mW maximum of 1555. The prism (Thorlabs PS853) has a listed transmittance of ~28% for both 1064 and 1555, so exiting the cavity there should be 17.9 mW of 1064 and 50 mW of 1555.
 
The cavity mirror transmits 32 ppm and 38 ppm of 1064 and 1555 respectively, so that puts the powers at 559 W and 1316 W inside the cavity. The beam sizes were both about 1700 μm 30 cm from the cavity, so their intensities are approximately:
 
<math> 770 </math> <math> MW/cm^2 </math> and <math> 1810 </math> <math> MW/cm^2 </math>
 
 

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