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arXiv · 2402.00349

High fidelity control of a many-body Tonks--Girardeau gas with an effective mean-field approach

Abstract

Shortcuts to adiabaticity (STA) are powerful tools that can be used to control quantum systems with high fidelity. They work particularly well for single particle and non-interacting systems which can be described exactly and which possess invariant or self-similar dynamics. However, finding an exact STA for strongly correlated many-body systems can be difficult, as their complex dynamics may not be easily described, especially for larger systems that do not possess self-similar solutions. Here, we design STAs for one-dimensional bosonic gas in the Tonks--Girardeau limit by using a mean-field approach that succinctly captures the strong interaction effects through a quintic nonlinear term in the Schrödinger equation. We show that for the case of the harmonic oscillator with a time-dependent trap frequency the mean-field approach works exactly and recovers the well-known STA from literature. To highlight the robustness of our approach we also show that it works effectively for anharmonic potentials, achieving higher fidelities than other typical control techniques.

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Muhammad S. Hasan, Thomás Fogarty, Jing Li, Andreas Ruschhaupt, Thomas Busch. 2024-04-04. High fidelity control of a many-body Tonks--Girardeau gas with an effective mean-field approach. https://doi.org/10.1103/physrevresearch.6.023114

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