I've now made a DCC page for the mirror specifications, all revisions should be reflected there.
Over the last couple of days, I've been playing around with Rana's coating optimization code to come up with a coating design that will work for us. The basic idea is a to use MATLAB's particle swarm constrained optimization tool to minimize an error function that is a composite of four penalties:
- Thermal noise - we use the proxy function from E0900068-v3 to do this
- Deviation from target T @1064nm, p-pol
- Deviation from target T @532nm, p and s-pol
- HR Surface field
On the AR side, I only considered 2 and 3. The weighting of these four components were set somewhat arbitrarily, but I seem to be able to get reasonable results so I am going with this for now.
From my first pass at it, the numbers I've been able to get, for 19 layer pairs, are (along with some plots):
HR Side:
- T = 50ppm, 1064nm p-pol
- T = 99%, 532nm s and p-pol
   (in this picture, the substrate is to the right of layer 38)
AR Side:
- R ~50ppm for 532nm, s and p-pol
  (substrate to the right of layer 38)
These numbers are already matching the specs we have on the DCC page currently. I am not sure how much better we can get the specs on the HR side keeping with 19 layer pairs...
All of this data, plus the code used to generate them, is on the gitlab coatings page...
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