Wetting transition in liquid helium.

We have used a vibrating wire microbalance technique to investigate the wetting of (3)He and (4)He on solid surfaces. Although superfluid (4)He wets solid substrates and forms a thick film, we find that films of (3)He and normal (4)He are limited to less than 13 layers. The lambda transition appears to be a wetting transition for (4)He.