Superfluid 4He dynamics beyond quasiparticle excitations
Other Condensed Matter
2016-08-03 v1
Abstract
The dynamics of superfluid 4He at and above the Landau quasiparticle regime is investigated by high precision inelastic neutron scattering measurements of the dynamic structure factor. A highly structured response is observed above the familiar phonon-maxon-roton spectrum, characterized by sharp thresholds for phonon-phonon, maxon-roton and roton-roton coupling processes. The experimental dynamic structure factor is compared to the calculation of the same physical quantity by a Dynamic Many-body theory including three-phonon processes self-consistently. The theory is found to provide a quantitative description of the dynamics of the correlated bosons for energies up to about three times that of the Landau quasiparticles.
Cite
@article{arxiv.1605.02638,
title = {Superfluid 4He dynamics beyond quasiparticle excitations},
author = {K. Beauvois and C. E. Campbell and J. Dawidowski and B. Fåk and H. Godfrin and E. Krotscheck and H. -J. Lauter and T. Lichtenegger and J. Ollivier and A. Sultan},
journal= {arXiv preprint arXiv:1605.02638},
year = {2016}
}
Comments
5 pages, 3 figures