Finite temperature effects in the Fermi liquid theory of the diffusion of ^{4} He in ^{3} HeH. H. Hjort, T. G. Culman, D. O. Edwards, and Jizhong He Physics Department, The Ohio State University, Columbus, Ohio, U.S.A. 43210 ( Submitted October 24, 1996 ) Abstract The diffusion coefficient D and the thermal diffusion ratio k_{T}, for dilute ^{4}He in liquid ^{3}He, are calculated from Fermi liquid theory. The collision integral assumes a scattering amplitude a^{34} expanded in scalar combinations of the quasiparticle momenta. As T -> 0, D varies as 1/T and k_{T}/c, where c is the concentration, approaches a constant. As shown previously, the limits for DT and k_{T}/c are determined by thermodynamic properties, the ^{4}He effective mass and partial volume, and properties of pure ^{3}He. We have decreased k_{T}/c by a few percent, by including the effect of simbol T on the ^{3}He distribution function. The temperature dependence of DT and k_{T}/c is linear and related to the coefficients in the expansion of a^{34}. Two coefficients can be found from thermodynamics. A conjecture about the remainder suggests that DT may have a maximum between 0 and 0.5K. |