Theory of anisotropic superfluidity in He^3

Anderson P.W., Brinkman W.F.

Recently we have shown that an anistropic Anderson-Morel state may be stabilized by feedback effects in the effective interaction arising from introduction of a gap in the spin-fluctuation spectrum. In this paper we determine the general form of the fourth-order term in the free energy owing to the above mechanism and use this result to make predictions regarding the phase diagram in the presence of a magnetic field and as a function of pressure.