2012/04/30 by Konstantin G. Zloshchastiev · 1 citation
Mathematics · Physics and Astronomy · #Atomic and Subatomic Physics Research #Classical mechanics #Cold Atom Physics and Bose-Einstein Condensates #Gaussian #Helium #Helium-4 #Mathematics #Parametric statistics #Phonon #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Roton #Statistical physics #Superfluid helium-4 #Superfluidity #Wavelength #cond-mat.other #physics.atm-clus #quant-ph
paper · pdf · doi:10.1140/epjb/e2012-30344-3
published as Eur. Phys. J. B (2012) 85: 273 · 9 pages, 6 figures
openalex publication_date 2012/08/01 · arxiv created 2012/08/10 · arxiv updated 2012/08/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We propose a theory which deals with the structure and interactions of volume elements in liquid helium II. The approach consists of two nested models linked via parametric space. The short-wavelength part describes the interior structure of the fluid element using a non-perturbative approach based on the logarithmic wave equation; it suggests the Gaussian-like behaviour of the element's interior density and interparticle interaction potential. The long-wavelength part is the quantum many-body theory of such elements which deals with their dynamics and interactions. Our approach leads to a unified description of the phonon, maxon and roton excitations, and has noteworthy agreement with experiment: with one essential parameter to fit we reproduce at high accuracy not only the roton minimum but also the neighboring local maximum as well as the sound velocity and structure factor.