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==Daily Log==
'''4/71/15'''
The beam quality is somewhat lacking with the orange laser, which makes it hard to match to the cavity mode--it's currently very poorly matched which is at least part of why I can't detect anything. It doesn't really behave as you'd expect when it's collimated. I checked how well it would focus--with a 40mm lens, I got to to about 30x60 micron diameter. The beam was about 5 mm before, so the diffraction limited spot should be closer to 10 microns. Still, we only need to focus to about 800 in the cavity, so no big deal hopefully. I'm vaguely trying to write a python thing so that I can say what initial beam I have and what I want to be and it tells me the best lenses to put where.
'''4/15/15'''
Been working on modulating the PCF output of the orange laser. Got the 1064 beam up and running again and locking as well as it used to. 780 was very easy to get modulated again, though it's always a little hard to actually detect with the lock-in. The 780 diode burned out--started outputting only a few mWs even at high current, but I replaced it and it's working fine again. I now have the 780, orange laser, and the HeNe aligned to the cavity using 2 flip mirrors. Each beam has two separate mirrors, but they're not all independent. Still, it was the cleanest setup I could come up with and after the initial difficult alignment it's not much of a problem. I'm trying to use a monochromator instead of the diffraction grating setup like before. I'm still chopping the beam and looking at it on the lock-in It works well enough for the 780 at least. My hope is that it will give me some sort of spectrum-resolving ability. I couldn't detect anything from the orange laser yet though--I think there's just too much unmodulated light getting through so that when I change its alignment to the cavity I'm mostly affecting how much light makes it through the monochromator. I got some low-pass filters though that should cut out everything but the modulated light though which will hopefully help. I haven't tried to make the beam-profile better match the 1064 yet either which will help increase conversion efficiency.
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