Simulations of sawtooth-wave adiabatic passage with losses

TL;DR

This paper presents simulations of Sawtooth-Wave Adiabatic Passage (SWAP) cooling, demonstrating its potential to significantly reduce population leakage compared to Doppler cooling, especially for narrow linewidth transitions and beam slowing applications.

Contribution

The study introduces simulation results showing that SWAP cooling can suppress population leakage more effectively than Doppler cooling, particularly in beam slowing and narrow linewidth regimes.

Findings

Leakage suppression is more effective in beam slowing than in thermal cooling.

Narrow linewidth transitions enhance leakage suppression.

SWAP can be effective even with branching ratios >10%.

Abstract

The results of simulations of cooling based on Sawtooth-Wave Adiabatic Passage (SWAP) are presented including the possibility of population leaking to states outside of the cycling transition. The amount of population leaking can be substantially suppressed compared to Doppler cooling, which could be useful for systems that are difficult to repump back to the cycling transition. The suppression of the leaked population was more effective when simulating the slowing of a beam than in cooling a thermal distribution. As expected, calculations of the leaked population versus branching ratio of spontaneous emission show that the suppression is more effective for narrow linewidth transitions. In this limit, using SWAP to slow a beam may be worth pursuing even when the branching ratio out of the cycling transition is greater than 10%.