Summary of work done over the last two days

1. Lightwave NPRO + controller moved to PSL table
   • ​​The interlock is not connected to the controller
   • Controller is not powered
2. Innolight NPRO + controller installed at endtable
   • ​​​​Interlock has been connected
   • For initial alignment purposes, I'm running it at an injection current of 1.000A (~50mW of IR out of the NPRO)
   • Temperature of crystal set to 31.66 degrees in anticipation of operation in the nominal state
3. Laying out optics
   • ​​Given that the mode out of the NPRO is different from that from the Lightwave, the mode-matching had to be re-done
   • Attachment #1 shows the mode-matching solution being implemented
   • Current state - I've placed all the optics up to and including the doubling crystal + oven. Alignment through IR Faraday is pretty good, QWP+HWP angles optimized to maximize transmission through the Faraday (<10% loss). Oven has been hooked up to temperature controller, and is currently set to 36.3 degrees. Coarse alignment into doubling crystal done at lower power. Even with the low IR power, I am able to see some green. It remains to turn the injection current up and do the fine alignment + lens position tweaking to maximize the green power from the doubling crystal - with ~1W of power, assuming 2%/W SHG efficiency, we should be seeing 20 mW of green (which is probably way too much)

Immediate next steps:

1. Some optimization to be done with regards to beam dumps for rejected beam from IR Faraday. Also double check to make sure that the reflected beam from L1 doesn't go back directly to the laser (at the moment it doesn't, is there a standard way to do this? I was trying to have the lens as close to normal incidence as possible, but I may not have been entirely successful which is why the reflected beam is not going straight back at the moment).
2. Optimize mode-matching into the doubling crystal
3. Once the desired green mode is obtained, continue with the rest of the layout
4. Update CAD drawing to reflect new layout