Superfluidity is a phenomenon in which a fluid has zero viscosity and can flow without any resistance or energy loss. This means that it has the ability to flow continuously without dissipating energy, even at extremely low temperatures.
Superfluidity occurs when a fluid is cooled to temperatures near absolute zero, where the particles in the fluid are able to condense into a single quantum state. This allows the particles to move in unison, without any collisions or friction, resulting in zero viscosity.
The most well-known example of a superfluid is liquid helium. Other examples include superfluid helium-3, ultracold atomic gases, and neutron stars.
Superfluidity has various practical applications, such as in cryogenics, where it is used to maintain low temperatures, and in superconductors, where it can enhance their performance. It is also being studied for potential use in quantum computing and other advanced technologies.
Some recommended books about superfluidity include "Superfluidity and Superconductivity" by D. R. Tilley and J. Tilley, "Quantum Liquids: Bose Condensation and Cooper Pairing in Condensed-Matter Systems" by A. J. Leggett, and "Superfluids" by K. H. Bennemann and J. B. Ketterson.