Evaporative cooling settings
Our evaporation ramp to a 87RB BEC (16 February 2009)
|Time (ms)||Final Frequency (MHz)||Power (Vcontrol)|
|1000||1.20||0.65 (lin. ramp)|
Things to remember:
- DDS likes to have continuous frequency ramps; make sure there are no jumps in frequency.
- The atoms like to have a continuous power of rf. Park the DDS at a single power, usually "50%" and use the variable attenuator to control the power.
- Check once in a while for spin mixtures. These are caused by too much or too little rf power near the end of the evaporation ramp. Find the happy medium.
- After finishing evaporation, ramp frequency back up to some high value (like, 5 MHz), with continuous power, before shutting off DDS
page revision: 9, last edited: 16 Feb 2009 18:38