On the problem of singlet superfluidity in 3He monolayers
Abstract
The problem of spin-singlet pairing and singlet superfluidity of a 3He monolayer on a 4He liquid film or a solid hydrogen surface is considered under the BCS approximation. It is shown that the critical parameters of the system can be determined in some cases by the short-wave values of the wave vectors (q ≃ qm > kF) rather than by Fermi values of these vectors of Bose particles (q ≃ kF) which lead to pairing. This considerably modifies the basic expressions for the energy gap and transition temperature. It is also shown that as a result of interaction with Rayleigh waves, the 3He monolayer on hydrogen surface can become a singlet superfluid layer at temperatures much higher than the transition temperature for a triplet superfluid state.