Cooling and trapping atoms using diode lasers (A)

Andrew G. Truscott

Nancy Jean Silva

Steven Chu, Mara Goff Prentiss, A. Cable +1 more

Carl Wieman

There has been considerable activity recently on cooling and trapping atoms using laser light. This work raises expectations that laser manipulation of atoms will be an important new tool for atomic physics. However, up to now, almost all the work has been on sodium atoms using light from dye lasers. The expense and complication of a narrowband dye laser system is a considerable limitation on the possible uses of this tool. In response to this we have been exploring the use of inexpensive diode lasers for the manipulation of atoms. We have found that diode lasers work very well for this purpose and even have some advantages over dye lasers in addition to cost and ease of use. We previously reported using light from diode lasers to stop a beam of atomic cesium. Here we discuss our more recent work using diode lasers to produce extremely cold cesium vapor via optical molasses cooling and the demonstration of a new type of optical trap. This is a purely optical spontaneous force trap which uses spatially inhomogeneous optical pumping to circumvent the optical Earnshaw theorem.

Steven Chu, Carl Wieman

Hidetoshi Katori, Fujio Shimizu

The laser cooling and trapping of argon and krypton isotopes in the 1s5 metastable state are demonstrated using stabilized diode lasers. Even isotopes of krypton are separately trapped by tuning the laser frequency. For Ar and 84Kr, approximately 6×105 and 1×105 atoms are trapped, respectively.