arXiv:2306.09238 · Physical Review A

Excited-state preparation of trapped ultracold atoms via swept potentials

Daniel J. Bosworth, Maxim Pyzh, Peter Schmelcher

Published Jan 12, 2024• 1 citation

Abstract

We study the out-of-equilibrium dynamics of noninteracting atoms confined within a one-dimensional harmonic trap triggered by dragging an external long-range potential through the system. The symmetry-breaking nature of this moving potential couples adjacent eigenstates in the atoms' effective potential, leading to an energy landscape reminiscent of systems exhibiting trap-induced shape resonances. These couplings may be exploited to selectively excite the atoms into higher vibrational states of the harmonic trap by controlling the motion of the dragged potential. To this end, we consider two protocols designs: The first protocol strives to maintain adiabaticity at critical points during the atoms' dynamics, while the second protocol utilizes the fast tunneling of the atoms within their effective double-well potential. These protocols take place in the few to many millisecond regime and achieve high-fidelity excitation of the atoms into pure vibrational states and superpositions thereof. Overall, our study highlights the significance of dragged potentials for controlling and manipulating atom dynamics and offers intuitive protocols for achieving desired excitations.

DOI: 10.1103/physreva.109.013311

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