Work
What we did today:
The laser is having further issues today.
When conducting experiments the day prior, it was working all morning until a couple of hours in when the beam stopped producing white light. The intensity of the beam had decreased so that there was no white light being produced. We knew that the laser was having issues, so we hypothesized that the laser was losing power over time. To check this, we set a power meter and logged what it read over the span of an hour, but noticed no change. This lead us to belive that the loss of power may be due to something in the beams path.
Some things we noted was that the laser's power was diminishing very fast with distance. We checked the mirrors first. It is expected that a laser loses about 2% of its power with every mirror it hits in its path. By checking the power before and after the first mirror we saw this to be true, so there are no problems with the mirrors. What we did notice, though, was that the power drastically decreased with distance.
We then used a beam profiler to look at the beam to try and see what was going on. This led us to encounter more issues. The beam seemed to be focus for certain PP (pulse picker) settings but not for others. This means that depending on which pulse picker setting you are in, the alignment of the optics does not hold.
We are still uncertain what the cause of these issues are.
What I plan to do tomorrow:
Continue to try to find the cause of these problems and how to account for them.