A valuable movie of 'Superfluid' helium experiment overturning common sense

"SuperfluidityIs a state in which the viscous resistance of the liquid has disappeared, a phenomenon that it spills out of the wall of the container and spills out, penetrates into a gap where one atom can finally pass, and a phenomenon that reverses various common sense is seen I will.

So, you can watch this interesting movie with liquid helium from the net. Playback is from the following.
5 min - Superfluid: Liquid Helium Phenomenon - Video

Although I do not know exactly what is amazing just by just watching the above movie, you can understand its awkwardness by reading the following explanation.

First of all superfluid transition.The University of Tokyo Low Temperature CenterAccording to the explanation, the liquid helium has a very low boiling point of 4.2 K (-269 ° C), so it seems to be boiling first, but when it comes to superfluid helium, friction disappears, so it entered from the outside Even if heat rises in temperature, it will be instantly cooled from the surroundings and eventually the heat will be carried by the gaseous helium evaporating from the liquid surface of the superfluid helium and the liquid level will be very quiet .Osaka City University Ultra Low Temperature LaboratoryofSuperfluid Helium 4It may be quite easy to understand this on the page description.

This is a boiling state


When it becomes superfluid helium, it gently quietly


Superfluid helium that climbs the wall with the next picture of startling. Explanation as to what kind of reasons it will beThe University of Tokyo Low Temperature CenterAccording to it, according to it, usually water molecules are pulled down because of the attraction between water molecules, that is, viscosity, but since superfluid helium has no friction, what kind of container of glass atoms It will be pulled by gravity, it will become a very thin layer at speeds of several tens of meters per second as it is climbing the wall of the glass container and drips down from the bottom part.

It is hard to believe that climbing up from this arrow and leaning from the bottom.


And the last is the fountain effect. When superfluid helium in the glass tube is heated, it transfers to the normal flow helium, the concentration of the superfluid helium decreases, the superfluid helium flows from the bottom into the glass tube and the liquid level rises. As a result, superfluid helium seems to blow out like a fountain.

The fountain effect seems to be in the middle


In addition, in addition to the aboveThe University of Tokyo Low Temperature CenterHigh-quality movies onUniversity of Toyama Cryogenic Quantum Science CenterThe Superfluid Helium Experimental Page has a movie of "Spider of Capizza". In everyday life there is a glimpse of a state of experiments that we never see before and it is very worthwhile.