Jizhong Finite temperature effects in the Fermi liquid theory of the diffusion of 4He in 3He

Анотація

The diffusion coefficient D and the thermal diffusion ratio k_T, for dilute ⁴He in liquid ³He, are calculated from Fermi liquid theory. The collision integral assumes a scattering amplitude a³⁴ 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 ⁴He effective mass and partial volume, and properties of pure ³He. We have decreased k_T/c by a few percent, by including the effect of simbol T on the ³He distribution function. The temperature dependence of DT and k_T/c is linear and related to the coefficients in the expansion of a³⁴. Two coefficients can be found from thermodynamics. A conjecture about the remainder suggests that DT may have a maximum between 0 and 0.5K.