149
edits
Zjs log: Difference between revisions
Jump to navigation
Jump to search
no edit summary
No edit summary |
No edit summary |
||
|
--[[User:Zjsimmons|Zjsimmons]] ([[User talk:Zjsimmons|talk]]) 17:46, 1 December 2014 (CST)
Yikes, it's Dec, where has the semester gone. I have the "1030" Fabry-Perot that we have from QC set up. It doesn't look that great, but hopefully works well enough for us to set up the PDH electronics. Planning to work on that tomorrow.
In the process of ordering mirrors and Invar to build 2 cavities that would be same dimensions, hopefully very similar to our ULE reference cavity. A spare may be of use to David on his experiment.
Re: 1055 laser, boo i can't seem to get any feedback from the set-up that i would have thought would have worked the best. I'm using the laser diodes from the order F325732 that Jared acquired. Number 2 diode, i was only able to get perhaps 20% feedback and there were definitely 2 lobes in the output mode for some collimations. As a result, i switched to the other diode, number 3 and it also appears to have structure on the output mode, less symmetrical lobes, but there is definitely a second spot you can see for some collimations. Now i can't seem to get any feedback. I've played with the collimation, grating angle, grating tilt(of course) cavity length, cleaned the diode and lens(the lens is kind of crappy), tried another lens, and still haven't seen any feedback, very strange. Perhaps the diodes are crappy, but i would sure like to get it working and see something working well before using our new 1055 wavelength-selected diode. We'll see, i could break down and try one of our new diodes.
--[[User:Zjsimmons|Zjsimmons]] ([[User talk:Zjsimmons|talk]]) 13:18, 28 November 2014 (CST)
A few updates. I spent much of last week modifying/constructing a lockbox for the PDH set-up utilizing the ULE cavity. I feel like i was able to apply some lessons learned from the last time around to aid assembly this time, principally putting it in a larger box made it easier to put together. Unfortunately, the cavity has a fatal problem and will be returned. They mirror glass is oriented the wrong direction giving structure on transmission and acting like a grating. Hopefully in the meantime we can get something else working to at least let us set up some of the electronics. Toward that end, we're working on two fronts:
b) I'm planning to build a temporary stop-gap cavity out of invar or super-invar with the same dimensions as our ULE cavity. I figure this would hopefully allow us to move forward while minimizing time lost as we don't really know how long it will take to get the ULE cavity replaced.
--[[User:Zjsimmons|Zjsimmons]] ([[User talk:Zjsimmons|talk]]) 17:03, 13 November 2014 (CST)
| |||