Measurement of Roton Energies and Linewidths inHe3-He4Solutions

Abstract

Using Raman scattering from rotons in liquid ${\mathrm{He}}^3$-${\mathrm{He}}^4$ solutions for ${\mathrm{He}}^3$ concentrations $0<~X<~0.11$ at $T=0.60\mathrm{}$ °K, we have measured the two-roton energy and linewidth. Our measurements indicate no change in the single-roton energy as a function of concentration, whereas the single-roton linewidth increases nonlinearly with $X$.