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--[[User:Zjsimmons|Zjsimmons]] ([[User talk:Zjsimmons|talk]]) 18:11, 5 November 2014 (CST)
I moved the SHG cavity, and launched into it with the revised laser and TA. Picked Nick's brain about mode-matching and had to refresh my memory on that. Wrote a quick script to get my bearings. Nick suggested having telescope lens on translation stage: that way that lens would help with beam size and the coupling lens close to the cavity would help with waist position. After messing with the lens and coupling tune-up, saw nice locking. I'm not sure why it worked well, but tuning up the cavity seemed to make it better. Perhaps the laser is better behaved and that is making a difference. Note: interestingly you can see noise (e.g. your voice) on the lock. Perhaps we should invest in sound insulation. Note2: unfortunately, for whatever reason, it seems like when the lock drops sometimes it rails the piezo; not ideal behavior.
--[[User:Zjsimmons|Zjsimmons]] ([[User talk:Zjsimmons|talk]]) 12:55, 3 November 2014 (CST)
OK, so last week i spent a lot of time building another laser. This one is basically the same as our go-to design, except the back of the mirror mount, adapter ring, and base-plate are all replaced by a single piece of aluminum. The collimation tube remains, but otherwise everything is one piece. The rational is that poor thermal conduction between the pieces in the former design may have been leading (in part) to poorer feedback and performance. Hopefully we will be able to evaluate the temperature performance somewhat with Eli's temp monitor project. Anyway, i just got the adjustment screws for it today so am getting ready to finish assembly and put it into service.
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