MASS-TRANSPORT IN THIN SUPERFLIUID HE-4 FILMS IN POROUS-MEDIA

Possibility to utilize thermal conductivity to study superfluid thin H e-4 films on porous glass has been examined in temperature range T=(0. 6-1.1)K. The detailed measurements performed for tile film in normal s tate call be qualitatively described by the ideal gas conductance In t ile superfluid state at T approximate to 0.6K a sharp increase of the temperature gradient along the sample at a critical heating power has been observed below T-c. This feature is similar to that at T approxim ate to 1K, where thermal conductivity technique is supposed to be appl icable.