Optics Express
Non-standard trajectories found by machine learning for evaporative cooling of 87 Rb atoms
Ippei Nakamura, Atsunori Kanemura, Takumi Nakaso, Ryuta Yamamoto, Takeshi Fukuhara
Abstract
Rb atoms. The evaporation trajectory was optimized to maximize the number of atoms cooled down to a Bose-Einstein condensate using Bayesian optimization. After 300 trials within 3 hours, Bayesian optimization discovered trajectories that achieved atom numbers comparable with those of manual tuning by a human expert. Analysis of the machine-learned trajectories revealed minimum requirements for successful evaporative cooling. We found that the manually obtained curve and the machine-learned trajectories were quite similar in terms of evaporation efficiency, although the manual and machine-learned evaporation ramps were significantly different.