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arXiv:2301.06461 · Physical Review A

Dynamical mean-field-driven spinor-condensate physics beyond the single-mode approximation

Jianwen Jie, Shan Zhong, Qimin Zhang, Isaiah Morgenstern, Hio Giap Ooi, Qingze Guan, Anita Bhagat, Delaram Nematollahi, Arne Schwettmann, D. Blume

Published May 11, 2023• 6 citations
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Abstract

$^{23}\mathrm{Na}$ spin-1 Bose-Einstein condensates are used to experimentally demonstrate that mean-field physics beyond the single-mode approximation can be relevant during the nonequilibrium dynamics. The experimentally observed spin oscillation dynamics and associated dynamical spatial structure formation confirm theoretical predictions that are derived by solving a set of coupled mean-field Gross-Pitaevskii equations [J. Jie et al., Phys. Rev. A 102, 023324 (2020)]. The experiments rely on microwave dressing of the $f=1$ hyperfine states, where $f$ denotes the total angular momentum of the $^{23}\mathrm{Na}$ atom. The fact that physics beyond the single-mode approximation at the mean-field level, i.e., spatial mean-field dynamics that distinguishes the spatial density profiles associated with different Zeeman levels, can, in certain parameter regimes, have a pronounced effect on the dynamics when the spin healing length is comparable to or larger than the size of the Bose-Einstein condensate has implications for using Bose-Einstein condensates as models for quantum phase transitions and spin squeezing studies as well as for nonlinear SU(1,1) interferometers.

DOI
10.1103/physreva.107.053309

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