For gaining about 3.45 mW of light after reflection from cavity on resonance when mode matching is about 60%, 8.63 mW light needs to fall at the cavity. There were three major obstacles in doing this which were resolved as follow:
Also, I have finally started an ATF wiki page to keep documentation of all RFPDs and changes to it. I'll make sure this page is updated and this page should be the reference point in future.
On another note, I'm seeing a steady decline of mode matching on both paths even when I'm staying far away from the alignment. Something is going on which needs to be fixed. After a discussion with awade, following are the suspects:
I'll fix the mode matching again before leaving today and will see if any big changes happen overnight.