Roton-Phonon Interactions in Superfluid 4He

Abstract

High-resolution neutron resonance spin-echo measurements of superfluid 4He show that the roton energy does not have the same temperature dependence as the inverse lifetime. Diagrammatic analysis attributes this to the interaction of rotons with thermally excited phonons via both four- and three-particle processes, the latter being allowed by the broken gauge symmetry of the Bose condensate. The distinct temperature dependence of the roton energy at low temperatures suggests that the net roton-phonon interaction is repulsive.

5 pages, accepted version

References in corpus (5)

• Bragg spectroscopy of a strongly interacting 85Rb Bose-Einstein condensate
• Magnon Decay in Noncollinear Quantum Antiferromagnets
• Spin-Wave Lifetimes Throughout the Brillouin Zone
• Direct current control of three magnon scattering processes in spin-valve nanocontacts
• Theory and data analysis for excitations in liquid ${}^4$He beyond the roton minimum

Cited by in corpus (13)

• Mutual Interactions of Phonons, Rotons, and Gravity
• The dispersion relation of Landau elementary excitations and the thermodynamic properties of superfluid ${}^4$He
• Ultracold neutron production and up-scattering in superfluid helium between 1.1 K and 2.4 K
• Microscopic dynamics of superfluid ${}^4$He: a comprehensive study by inelastic neutron scattering
• Superfluid 4He dynamics beyond quasiparticle excitations
• Emergent particles and gauge fields in quantum matter
• Beyond mean-field corrections to the quasiparticle spectrum of superfluid Fermi gases
• Anomalous thermal decoherence in a quantum magnet measured with neutron spin-echo spectroscopy
• Roton excitations and the fluid-solid phase transition in superfluid 2D Yukawa Bosons
• Ultrafast non-equilibrium dynamics of rotons in superfluid helium
• Breakdown of sound in superfluid helium
• Damping of elementary excitations in one-dimensional dipolar Bose gases
• Quasiparticle disintegration in fermionic superfluids