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arXiv · 2007.06977

Towards a QMC-based density functional including finite-range effects: excitation modes of a $^{39}$K quantum droplet

V. Cikojević·L. Vranješ Markić·M. Pi·M. Barranco·J. Boronat
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Abstract

Some discrepancies between experimental results on quantum droplets made of a mixture of $^{39}$K atoms in different hyperfine states and their analysis within extended Gross-Pitaevskii theory (which incorporates beyond mean-field corrections) have been recently solved by introducing finite-range effects into the theory. Here, we study the influence of these effects on the monopole and quadrupole excitation spectrum of extremely dilute quantum droplets using a density functional built from first-principles quantum Monte Carlo calculations, which can be easily introduced in the existing Gross-Pitaevskii numerical solvers. Our results show differences of up to $20\%$ with those obtained within the extended Gross-Pitaevskii theory, likely providing another way to observe finite-range effects in mixed quantum droplets by measuring their lowest excitation frequencies.

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V. Cikojević, L. Vranješ Markić, M. Pi, M. Barranco, J. Boronat. 2020-07-14. Towards a QMC-based density functional including finite-range effects: excitation modes of a $^{39}$K quantum droplet. https://doi.org/10.1103/physreva.102.033335

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