Counting Atoms

I tuned the laser again to maximize absorption and minimize mode hopping.  Just in case it shifts again and I have to tune it again, I will wait to run the laser through the AOM system again.  Despite my efforts, I couldn’t get saturated absorption in the krypton cell.  I think I will need another person helping me for this, as I cannot see the oscilloscope from where the krypton tube is.  It should be close though.  Also, the wavemeter wasn’t working today.  The computer is running slow so it could just be that the computer needs to be restarted.

The laser seems to be multimodal again.  Something must have shifted again.  I am in the process of readjusting.

Today I did some serious adjusting to the vertical tilt on the grating, using an oscilloscope to be very precise in getting the best possible alignment.  This was risky, as I may have lost the absorption line.  Luckily I retained it with extremely powerful output and absorption.  The mode hopping is much less now.  However, now the AOM system is out of alignment and will need configuration.  I was also unable to find saturated absorption.  I switched the krypton tubes before I adjusted the tilt to see if I would have more luck with the lower pressure tube, but I couldn’t even see the absorption with it - so I switched back to the higher pressure tube.  Perhaps with the new alignment I will have more luck with the lower pressure tube.

I found the absorption wavelength to be 811.30nm and maximized the output in the AOM system and the cardboard box system.  I also turned on the turbo pump in the proper manner.

I turned the mechanical pump on and tuned up the system.