Numerical Study of Evaporative Cooling in the Space Station

TL;DR

This study uses numerical simulations to analyze how mechanical vibrations and magnetic fields affect evaporative cooling in space station conditions, providing insights for future cold atom experiments in space.

Contribution

It introduces a detailed numerical analysis of evaporative cooling under space station conditions, including effects of vibrations and magnetic fields, with specific simulation results.

Findings

Vibrations significantly increase atomic losses during cooling.

Magnetic field enhancement improves phase space density.

Achieved ultra-low temperatures of 8 pK with optimized conditions.

Abstract

In this paper, we numerically studied the effects of mechanical vibration and magnetic fields on evaporative cooling process carried in space station by direct simulation Monte Carlo method. Simulated with the vibration data of international space station, we found that the cooling process would suffer great atomic losses until the accelerations reduced tenfold at least. In addition, if we enlarge the s-wave scattering length five times by Feshbach resonance, the PSD increased to 50 compared to 3 of no magnetic fields situation after 5 seconds evaporative cooling. We also simulated the two stages crossed beam evaporative cooling process (TSCBC) under both physical impacts and obtain $4\times10^5$ $^{85}$Rb atoms with a temperature of 8 pK. These results are of significance to the cold atom experiments carried out on space station in the future.