What is a superfluid?
Superfluid is the phase of matter capable of flowing infinitely without loss of energy. This feature of some isotopes was discovered by Pyotr Leonidovich Caps', John F. Allen and Don Misener in 1937.
Only liquids and gases can be superfluids. For example, the Helia freezing point is 1 K (Kelvin) and 25 pressure atmosphere, the lowest of any element, but the substance begins to show superfluid properties at approximately 2 K. This happens when the atoms are placed very close to each other and cool down so much that their quantum wave function begins to overlap and atoms lose their individual identity and behave more as a single super-atom.
Limiting factor on which materials can show redundancy and which cannot be that the material must be very cold (less notPs 4 k) and at this cold temperature the liquid remains. Materials that become fixed at low temperatures cannot assume this phase. When cooling at very low temperatures, a set of bosons ready for superfluid, atoms with an even number of nucleons, forms into the condensate of the bose-einstein, the superfluid phase of matter. When fermions, atoms with an odd number of nucleons, such as the isotop Helia-3, cool down to several Kelvins, it is not enough to cause this transition.
Because only bosons can easily become a bose-einstein condensate, fermiions must first pair each other to become a superfluid. This process is similar to pairing of Cooper electrons that occur in superconductors. When two atoms with an odd number of nucleons pair, they still have a dull nucleon and start to behave like bosons, condense together to a superfluid state. This is called fermion condensate and appears only at the temperature of MK (Milikelvin), rather than several Kelvins. KeyThe pairing of the atom in the superfluid and the pairing of electrons in the superconductor is that the atomic pairing is mediated more by fluctuations of quantum spin than by replacing phonon (vibrating energy).
Superfluids have some impressive and unique properties that distinguish them from other forms of matter. Because they have no inner viscosity, a vortex created within one persists forever. Superfluid has zero thermodynamic entropy and endless thermal conductivity, which means that there can be no temperature differential between two superfluids or two parts of the same parts. They can also climb up and out of the container in a layer of one atom thickness unless the container is sealed. The conventional molecule built into the superfluid can move with fully crippling freedom, acting like gas. Other interesting features may be discovered in the future.
Most of the so -called superfluids are not clean, but in fact they are a mixture of liquid ingredients and superfluid components. Potential SUP applicationsRfluids are not as exciting and extensive as superconductors' applications, but the dilution of refrigerators and spectroscopy are two areas where they have found use. Perhaps the most interesting applications today are purely educational and show how quantum effects can become macroscopic under certain extreme conditions.