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Tara noticed an accidental re-definition in my old code. I fixed it, and updated the svn. This fixes most of the discrepancies, but shifts the difference in thermo-optic to the low-frequency region.
Attachment 1 is the comparison from case 3 between mine and Tara's calculations of his optimized coating structure.
Attachment 2 is the comparison from case 2 between mine and Tara's calculations of a 55-layer 1/4-wavelength stack.
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I discussed the calculation with Matt. The error in TO noise is large because it is a fraction of something small. Mostly it comes from TE part. The error in TO noise appears large (10%-20%) because the TO level is small. Otherwise, the rests are in good agreement, and I think we should be able to order soon.
Below, summary of the calculation, dTE is alpha_effective * coating thickness, dTO is beta effective * lambda. 0.2% difference in dTE and 0% difference in dTR can cause error upto 40% in dTO when dTE and dTR cancel each other really well. But this will be insignificant, since the final TO levels are still in the same magnitude.
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Matt |
Gwinc |
| dTE |
8.161e-11 |
8.141e-11 |
| dTR |
-8.11e-11 |
-8.11e-11 |
| dTO (dTE+dTR) |
4.87e-13 |
2.88e-13 |
The summary of the TO cancellation is in wiki page AlGaAs |