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arXiv:2405.07492 · PRX Quantum

Laser-Painted Cavity-Mediated Interactions in a Quantum Gas

Mariano Bonifacio, Francesco Piazza, Tobias Donner

Published Dec 2, 2024• 6 citations
arXivHTMLPDF

Abstract

Experimental platforms based on ultracold atomic gases have significantly advanced the quantum simulation of complex systems, yet the exploration of phenomena driven by long-range interactions remains a formidable challenge. Currently available methods utilizing dipolar quantum gases or multimode cavities allow us to implement long-range interactions with a 1 / r 3 character or with a spatial profile fixed by the mode structure of the vacuum electromagnetic field surrounding the atoms, respectively. Here, we propose an experimental scheme employing laser-painted cavity-mediated interactions, which enables the realization of atom-atom interactions that are fully tunable in range, shape, and sign. Our approach combines the versatility of cavity quantum electrodynamics with the precision of laser manipulation, thus providing a highly flexible platform for simulating and understanding long-range interactions in quantum many-body systems. Our analytical predictions are supported by numerical simulations describing the full dynamics of the atoms, the laser, and the cavity. These reveal the self-organization of domains in the density of the atomic cloud, confirming the finite-range nature of the induced interactions. We demonstrate that there is a wide and experimentally accessible parameter regime in which our protocol works robustly, with negligible heating of the quantum gas. The methodology not only paves the way for exploring new territories in quantum simulation but also enhances the understanding of fundamental physics, potentially leading to the discovery of novel quantum states and phases. Published by the American Physical Society 2024

DOI
10.1103/prxquantum.5.040332

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