Thermal Conductivity of 3He confined in a 1.1 micron sized channel.*

We describe the results of experiments on the thermal conductivity of 3He confined to a nanofabricated channel of ~1.1 um height, fabricated in silicon that is anodically bonded to glass. The channel separates a 3He filled chamber of small volume containing a fork thermometer/heater from a separate chamber with a silver heat exchanger filled with 3He, which contains an identical fork thermometer. In the normal state of 3He at low pressure, an anticipated crossover from Fermi-liquid (inelastic scattering length varying as T^-2) to mean free-path-limited behavior (scattering length dominated by boundary scattering) is observed. In the superfluid, the presence of two-fluid flow near T_c is investigated and the supercooling and nucleation of the B phase from the A phase in the viciniy of the polycritical point is explored.