A dense Bose fluid at zero temperature: condensation and clusters in liquid He-4

V I Kruglov; M J Collett

doi:10.1140/epjd.e2014-40535-7

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arXiv · 1307.7453

A dense Bose fluid at zero temperature: condensation and clusters in liquid He-4

V I Kruglov·M J Collett

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Abstract

We present a full set of wave equations describing a dense Bose fluid, applicable both to non- ideal gases and to liquid 4He. The phonon spectrum in liquid 4He is found and the fraction of condensed particles is calculated at zero temperature for a wide range of densities. The theory also yields the ground-state energy for the quantum liquid 4He in agreement to high accuracy with Monte Carlo simulations and experimental data at low pressure. We also present the derivation of a generalized Hartree-Fock equation describing roton clusters in low temperature liquid 4He, allowing us to confirm that, at low enough temperatures and for a wide range of pressures, the stable clusters consist of 13 bound atoms.

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BibTeX RIS

V I Kruglov, M J Collett. 2013-07-29. A dense Bose fluid at zero temperature: condensation and clusters in liquid He-4. https://doi.org/10.1140/epjd.e2014-40535-7

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