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arXiv · 1701.06789

Efficient description of Bose-Einstein condensates in time-dependent rotating traps

Matthias Meister·Stefan Arnold·Daniela Moll·Michael Eckart·Endre Kajari·Maxim A. Efremov·Reinhold Walser·Wolfgang P. Schleich
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Abstract

Quantum sensors based on matter-wave interferometry are promising candidates for high-precision gravimetry and inertial sensing in space. The favorable source for the coherent matter waves in these devices are Bose-Einstein condensates. A reliable prediction of their dynamics, which is governed by the Gross-Pitaevskii equation, requires suitable analytical and numerical methods which take into account the center-of-mass motion of the condensate, its rotation and its spatial expansion by many orders of magnitude. In this chapter, we present an efficient way to study their dynamics in time-dependent rotating traps that meet this objective. Both, an approximate analytical solution for condensates in the Thomas-Fermi regime and dedicated numerical simulations on a variable adapted grid are discussed. We contrast and relate our approach to previous alternative methods and provide further results, such as analytical expressions for the one- and two-dimensional spatial density distributions and the momentum distribution in the long-time limit that are of immediate interest to experimentalists working in this field of research.

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Matthias Meister, Stefan Arnold, Daniela Moll, Michael Eckart, Endre Kajari, Maxim A. Efremov, Reinhold Walser, Wolfgang P. Schleich. 2017-01-24. Efficient description of Bose-Einstein condensates in time-dependent rotating traps. https://doi.org/10.1016/bs.aamop.2017.03.006

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