We derive scaling laws for the number of atoms, collision rate, and phase-space density as a function of trap depth for evaporative cooling in an adiabadically lowered optical trap. The results are in excellent agreement with a Boltzmann equation model and show that very large increases in phase-space density can be obtained without excessive slowing of the evaporation rate. Predictions are in reasonable agreement with a recent experiment that achieves Bose-Einstein condensation by evaporation in an optical trap. We also discuss evaporation of fermionic mixtures and explain why Pauli blocking does not strongly inhibit cooling.
|Original language||English (US)|
|Number of pages||1|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|State||Published - Jan 1 2001|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics