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Chinese Physics B

One-dimensional atom laser in microgravity*

Yi Qin, Xiaoyang Shen, Xia Lin

Published May 8, 2021• 1 citation
Publisher

Abstract

Using coupled Gross–Pitaevksii (GP) equations, we simulate the output of one-dimensional pulsed atom laser in space station. We get two atom laser pulses propagating in opposite directions with one pulsed RF coupling. Compared with atom laser under gravity, the laser pulse in microgravity shows much slower moving speed, which is suitable to be used for long-term investigations. We also simulate the output flux at different coupling strengths.

DOI
10.1088/1674-1056/abff25

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Using coupled Gross–Pitaevksii (GP) equations, we simulate the output of one-dimensional pulsed atom laser in space station. We get two atom laser pulses propagating in opposite directions with one pulsed RF coupling. Compared with atom laser under gravity, the laser pulse in microgravity shows much slower moving speed, which is suitable to be used for long-term investigations. We also simulate the output flux at different coupling strengths.
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Atom lasers based on rf outcoupling from a trapped Bose-Einstein condensate can be described by a set of generalized, coupled Gross-Pitaevskii equations (GPEs). If not only one but two radio frequencies are used for outcoupling, the atoms emerging from the trap have two different energies and the total wave function of the untrapped spin state is a coherent superposition which leads to a pulsed atomic beam. We present results for such a situation obtained from a one-dimensional GPE model for magnetically trapped 87Rb{}^{87}\mathrm{Rb}87Rb in the F=1F=1F=1 state. The wave function of the atomic beam can be approximated by a sum of two Airy functions. In the limit of weak coupling we calculate the intensity analytically.
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