Year: 2025
Type: article
Abstract: We observe entanglement between collective excitations of a Bose-Einstein condensate in a configuration analogous to particle production during the preheating phase of the early Universe. In our setup, the oscillation of the inflaton field is mimicked by the transverse breathing mode of a cigar-shaped condensate, which parametrically excites longitudinal quasiparticles with opposite momenta. After a short modulation period, we observe entanglement of these pairs that reveals the role played by vacuum fluctuations in seeding the parametric growth, confirming the quantum origin of the excitations. As the system continues to evolve, we observe a decrease in correlations and a disappearance of nonclassical features. These point toward future experimental probes of the late-time nonlinear regime where further analogies can be drawn with reheating, i.e., the thermalization of the postinflationary Universe.
Source: Physical Review Letters
DOI: 10.1103/h7ws-g9z2
Authors: Victor Gondret, Clothilde Lamirault, Rui Dias, Léa Camier, Amaury Micheli, Charlie Leprince, Quentin Marolleau, Jean-René Rullier, Scott Robertson, Denis Boiron, Christoph I. Westbrook
Institutions: Centre National de la Recherche Scientifique, Université Paris-Saclay, Institut d’Optique Graduate School, Laboratoire Charles Fabry, RIKEN, RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences, École Nationale Supérieure de Mécanique et d'Aérotechnique, Institut Pprime, Université de Poitiers
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4416260824