Binding of He3 in He4 films

We present for the first time a calculation of the binding of He3 to films of He4. We follow a variational procedure which has been used successfully for calculating the binding of He3 to the surface of bulk He4. Our main modifications consist of the inclusion of the substrate van der Waals field as a local pressure within the film and as an attractive tail in the vacuum region above the surface. We compare the solution for the bound-state energies with experimental results for films and find reasonable agreement for the binding energy. Our calculation and experimental results suggest that models of He3 in films of He4, where the He3 is assumed to be in a continuum of three-dimensional states, are not strictly correct.