Effect or He-3 on submonolayer superfluidity - art. no. 045301

We have studied the superfluid response of He-3-He-4 mixture films adsorbed onto porous gold for a wide range of He-3 and He-4 coverages, focusing on submonolayer superfluidity. At T = 0, He-3 appears to float on top of He-4 and can be viewed as a second substrate that induces its own inert layer. D epending on the He-4 content, the zero-temperature superfluid mass and the superfluid onset temperature either saturate or vanish with the addition of He-3. The T = 0 superfluid-insulator phase boundary, which can be describe d by a simple function, is Found in the He-3-He-4 coverage plane.