Ruquan Wang

Ruquan Wang's picture
Associate Professor
Institute of Physics, Chinese Academy of Sciences
Research Areas: 
Atomic Physics
Education: 
Ph.D. 2006, Yale University
Advisor: 
Mark Kasevich
Dissertation Title: 
Approaching lithium BEC with a mini trap
Dissertation Abstract: 

I will discuss the various experimental techniques to achieve BEC of bosonic 7Li. The emphasis is on the Mini trap.

A Mini trap is a DC Ioffe-Pritchard type of magnetic trap of a few millimeters scale. With a size much smaller than the traditional magnetic trap, it has a comparable confinement, but dissipates 2-3 orders of magnitude less power. At 100A, it dissipates about 7W and has a trap depth of 70G. Because its trapping volume is comparable to the size of the MOT, an effective transfer from the MOT to the magnetic trap is easily achieved. We can easily transfer 2 ∗ 108 atoms to the trap, which is 2 orders of magnitude more than a typical Micro trap. The Mini trap is immunized to the surface interaction problem of Micro trap. Its trap life-time is about 90 seconds at 78A while a typical Micro trap life-time is only 5 seconds.

Also mentioned is a proposed broadband optical slower. The unique advantage of the broadband optical slower is that we can achieve transverse cooling and longitudinal slowing at the same time, which can increase the cold atom beam flux by 2 orders of magnitude. Broadband optical slower does not need a strong magnetic field, unlike the Zeeman slower, which can be very important for precise measurement experiments.