Magneto-Optical Trap

By using carefully controlled lasers and magnetic fields, atoms can be slowed down from their normal frenzied activity and trapped as an extremely cold cloud. In the summer of 2009, Judith Olson '11 and I embarked on a project to build a Magneto-Optical Trap (MOT) apparatus. The MOT traps Rubidium atoms at a temperature within a fraction of a degree of absolute zero. Our first goal was to build the electronic and mechanical system to produce laser light of a precisely controlled frequency. Following that we built the optical apparatus to produce the MOT and made measurements of the cold cloud. Judith worked on this project as her senior thesis for the BS degree. In the summer of 2011, Ryan Jefferis '12 worked on improving the temperature stability of the lasers and Josh Cheng '14 worked on reducing noise in the laser light sensors. Joey Engelbrecht ’13 made carful measurements of the number of atoms and density as a function of trapping field and laser detuning. Megan Kelleher ’15 rebuilt the beamline with improved components giving a larger atom cloud. Jon Smucker ’16 built a computerized control system and measured the temperature of the cloud. Oliver Vischer ’16 built a Fabry-Perot interferometer which allows more precise control of the laser frequency. Matt Bellardini ’17 built a robust temperature controller to stabilize the laser temperature drift.