A Laser Trap for Neutral Atoms
Abstract
The purpose of this project is to construct and study a laser trap for neutral atoms, initially potassium (K). At low densities, such a trap could be used to address a number of fundamental questions, e.g., the interaction of an individual atom with an electromagnetic field, collision dynamics and recombination. The feasibility and limitations of a purely laser trap concept, a corner cube trap, are studied for trapping neutral K atoms. The confinement of the atoms in the two dimensions perpendicular to the laser will be provided in the cavity of a high power alexandrite laser operating in the ('doughnut mode') tuned slightly to the blue side of the 4s 2S1/2 to 2P3 resonance line of the K atom. By reflecting the laser back on itself with two mirrors, one caps the ends of the cylindrical trap, resulting in a slightly weaker end plug. This trap concept employs not laser cooling, but rather counterstreaming 4He atoms which are cooled to about 1.5 K, to drastically cool the K atoms to thermal energies well below the trap depth (expected to be about 10 K). Various loss mechanisms for the trapped atoms are studied. In particular, K atoms can be lost to the trap if they are multiphoton ionized, if they are heated by absorption and emission of many photons ('recoil' or 'diffusional' heating), if they simply have much higher energy than the vast majority of other atoms at 1.5 K, or if they recombine with He atoms to form KHe (or KHe2, etc.).
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 12, 1985
- Accession Number
- ADA161834
Entities
People
- William C. Stwalley
Organizations
- University of Iowa