Counting Atoms

I’ve got everything locked.  The slave is at full power (200.6 mA) and the temperature is set to .733.  I’m going to go play with the optics of the slave.  The gain is set to 2.9, its been locked for about 10 minutes.  I then locked it again and the gain is now set to 20.0, but the sensitivity has been lowered (or increased whichever one makes the signal smaller)  The power I’m getting out of the slave on the handy dandy dial powermeter is about 60 mW.  This seems odd, so I would like to validate it with another meter.

Ben

I’ve tuned the laser, but am still getting some of variation; I’m going to send the laser through the optical equipment, and check for absorption after that.  It is going between 811.294 and 811.299.  The current is 152.7 and the temperature is set to 0.772.

I was in lab today and absorbtion remained stable and on maximum level.

After slight changes in current to maximaze the absorption, that changed from the last time,  the temepertaure changed bit and absorptionn is only partial. I hope that slight change in temperature will bring success.

I found it, everything is totally absorbed. Wavelength is jumping between .29  and .30 and temp voltage is 1.254V with current 58.6mA. I hope that the system will stay stable!

The absortpion from last time was gone and I couldn’t find it by adjusting current. So I changed temperature litlle bit and then turned the grating as the wavelegth was to far from desired value. I continued with searching but it was not succesfull this time.

I am still in the process of getting the laser to 811.29nm.  However, I cannot seem to get the laser out of the 812 - 813 range.  Unfortunately, the wavemeter can only scan over a small range of grating adjustment, so I must constantly go back and forth realigning the laser and checking the wavelength.  I would benefit greatly from the rough spectrometer in the optics lab, as it doesn’t require the system to be lined up in order to use.  I could use it to get in the right range and then use the precise wavemeter to make a more exact match.  I could also use the power meter for adjusting vertical tilt.

I found the absorption today. Laser seems to be in a single mode and amplitude of piezo-system is set to zero now. Temperature is set to 1.285V (1.299 on the second output) and actual current is 70.4 mA. I hope that the system will be stable now and that it’s not gonna disappear. Wavelength is at the value of 811.29 nm.

Today, I reached the absorption many times, but it was unfortunately transient states all the time. However, by changing temperature and angle of grating, I was every time on wavelengths about .29 - .30 so this the zone where the real absorption would be found, according to me.

I scanned throw few different temperatures but I couldn’t get the absorption. I am afraid that next time I will have to change the angle of grating and start from the beginning.