The intensity noise that I have noticed after the EAOM installation disappeard with the use of a PBS before it.
Has to be mentioned that the light coming from the EAOM becomes eliptical with following power ratios at the PBS after theEAOM:
Pinc = 1.59mW (p-polarized);
Ptrans = 1.30mW (p);
Prefl = 0.25mW (s);
We were steering the beam transmitted from the cavities with use of lenses. I have realigned (not easy thing with such space constrains).
Intensity noise is way better, although the overall noise did not improved as the intensity noise is not the limiting noise. I think we need to suppress
more free-running noise. Actually I will go back to our FSS servo because I think we need different performances (not for now).
I have accidentally misaligned the north cavity, better not to say how :-);
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