화학공학소재연구정보센터
Science, Vol.278, No.5338, 664-666, 1997
Superfluid Droplets on a Solid-Surface
Photographs are presented of isolated superfluid helium-4 droplets prepared on a cesium surface, the only material known that is not wetted by superfluid helium. Although thermodynamic measurements show that the cesium surface is highly uniform, the contact angle of the droplets is extremely hysteretic and depends on whether the contact line is advancing or receding. Superfluid helium-4 droplets on an inclined surface do not flow downhill but rather are strongly pinned to the surface.