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Thermal behavior of Bose-Einstein condensates of polar molecules

J. Sánchez-Baena1,*, G. Pascual1, R. Bombín2, F. Mazzanti1, and J. Boronat1

  • *Contact author: juan.sanchez.baena@upc.edu

Phys. Rev. Research 7, 033080 – Published 21 July, 2025

DOI: https://doi.org/10.1103/9sbg-6qqw

Abstract

We use the finite-temperature extended Gross-Pitaevskii equation (TeGPE) to study a condensate of dipolar NaCs molecules under the conditions of the recent breakthrough experiment [Bigagli et al., Nature 631, 289 (2024)]. We report the condensate fraction of the system and its density profile after a time-of-flight expansion for the coldest experimental case, finding excellent agreement with the experimental measurements. We also report the peak density of the ground state and establish a comparison with the experimental estimates. Our results, derived from the TeGPE formalism, successfully describe the Bose-Einstein condensation of polar molecules at finite temperature.

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