Relation between the temperature gradient and concentration gradient in superfluid 3He–4He mixtures

Abstract

The temperature and concentration gradients ∇T and ∇x created by a heat flow in a superfluid 3He–4He mixture with a concentration of 9.8% 3He are measured in the steady state in the temperature range T=70–500 mK. It is found that the ratio ∇x/∇T obtained in the experiment can be described on the basis of a dependence of the osmotic pressure on the temperature and concentration. The data are used to find the thermodiffusion ratio and, hence, the thermodiffusion coefficient of this mixture.