Abstract
Interactions between excitations in superfluid helium are investigated by Green's function techniques. In our model, a sharp peak appears in the two-excitation spectrum corresponding to a resonance of two rotons. Interaction of the resonance with the single-particle spectrum results in a hybridization and splitting of the one-particle spectrum into two distinct branches. These theoretical results are in agreement with recent neutronscattering and Raman-scattering experiments.
- Received 2 June 1970
DOI:https://doi.org/10.1103/PhysRevLett.25.333
©1970 American Physical Society