Nonlinear excitations in a film of a mixture of 3He and superfluid 4He

Using a combination of the superfluid [sup 4]He film model of Rutledge et al. and the layered model of Guyer and Miller the authors have investigated the nonlinear excitations in a film of a mixture of [sup 3]He and superfluid [sup 4]He. They have shown that such a system allows one-dimensional soliton excitations. These solitons, however, are not stable with respect to transverse perturbations. In that case the system allows two-dimensional lump solutions. 7 refs.