Heat conduction in spin polarized gaseous helium-3 : Recent theoretical and experimental results

Abstract

Abstract The transport properties of dilute spin polarized gases exhibit interesting dependences on the polarization M at low temperature, due to quantum indistinguishability between colliding particles. For the heat conduction κ of polarized gaseous helium 3, recent calculations have checked the convergence of the moment expansion of the out of equilibrium density matrix. Four to five moments are necessary to achieve a 1% accuracy. At the same time the changes of κ with M have been reliably measured in the l.3–4.2 K range, with great care to control all the heat fluxes reaching the cell. The temperature dependence of the changes Of κ with M is now found in satisfactory agreement with theory.