Helium II will "creep" along surfaces in order to find its own level - after a short while, the levels in the two containers will equalize. The Rollin film also covers the interior of the larger container; if it were not sealed, the helium II would creep out and escape.

Superfluidity is a phase of matter or description of heat capacity in which "unusual" effects are observed when liquids, typically of helium-4 or hydrogen, overcome friction by surface interaction when at a stage, known as "lambda point", at which the liquid's viscosity becomes zero. Also known as a major facet in the study of quantum hydrodynamics, it was discovered by Pyotr Leonidovich Kapitsa, John F. Allen, and Don Misener in 1937 and has been described through phenomenological and microscopic theories. Image File history File links Helium-II-creep. ... Image File history File links Helium-II-creep. ... A Rollin film is a 30 nm thick liquid film of Helium in the Helium II state. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A liquid will assume the shape of its container. ... Helium-4 is a non-radioactive and light isotope of helium. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... For other uses, see Friction (disambiguation). ... Lambda point is the temperature (approximately 2. ... Viscosity is a measure of the resistance of a fluid to deform under shear stress. ... Look up zero in Wiktionary, the free dictionary. ... Quantum hydrodynamics is more than the study of superfluidity. ... Semenov (on the right) and Kapitsa (on the left), portrait by Boris Kustodiev, 1921 Pyotr Leonidovich Kapitsa (Russian Пётр Леонидович Капица) (July 9, 1894 – April 8, 1984) was a Soviet/Russian physicist who discovered superfluidity with some contribution from John F. Allen and Don Misener in 1937. ... John F. Allen (May 5, 1908-April 22, 2001 was a scientist. ... Don Misener was a physicist. ... Year 1937 (MCMXXXVII) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar. ... The term phenomenology in modern science, especially in physics, is used to describe a body of knowledge which relates several different empirical observations of phenomena to each other, in a way which is consistent with fundamental theory, but is not directly derived from theory. ...

Background

Although the phenomenologies of the superfluid states of helium-4 and helium-3 are very similar, the microscopic details of the transitions are very different. Helium-4 atoms are bosons, and their superfluidity can be understood in terms of the Bose statistics that they obey. Specifically, the superfluidity of helium-4 can be regarded as a consequence of Bose-Einstein condensation in an interacting system. On the other hand, helium-3 atoms are fermions, and the superfluid transition in this system is described by a generalization of the BCS theory of superconductivity. In it, Cooper pairing takes place between atoms rather than electrons, and the attractive interaction between them is mediated by spin fluctuations rather than phonons. See fermion condensate. A unified description of superconductivity and superfluidity is possible in terms of gauge symmetry breaking. Helium-3 is a non-radioactive and light isotope of helium. ... Properties For alternative meanings see atom (disambiguation). ... In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... For other topics related to Einstein see Einstein (disambig) In statistical mechanics, Bose-Einstein statistics determines the statistical distribution of identical indistinguishable bosons over the energy states in thermal equilibrium. ... A Bose–Einstein condensate is a phase of matter formed by bosons cooled to temperatures very near to absolute zero (0 kelvins or -273. ... In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... BCS theory (named for its creators, Bardeen, Cooper, and Schrieffer) successfully explains conventional superconductivity, the ability of certain metals at low temperatures to conduct electricity without resistance. ... A Cooper pair is the name given to electrons that are bound together in a certain manner first described by Leon Cooper. ... Properties The electron (also called negatron, commonly represented as e−) is a subatomic particle. ... In physics, spin refers to the angular momentum intrinsic to a body, as opposed to orbital angular momentum, which is the motion of its center of mass about an external point. ... Normal modes of vibration progression through a crystal. ... It has been suggested that this article or section be merged with fermionic condensate. ... Spontaneous symmetry breaking in physics takes place when a system that is symmetric with respect to some symmetry group goes into a vacuum state that is not symmetric. ...

Superfluids, such as supercooled helium-4, exhibit many unusual properties. A superfluid acts as if it were a mixture of a normal component, with all the properties associated with normal fluid, and a superfluid component. The superfluid component has zero viscosity, zero entropy, and infinite thermal conductivity. (It is thus impossible to set up a temperature gradient in a superfluid, much as it is impossible to set up a voltage difference in a superconductor.) One of the most spectacular results of these properties is known as the thermomechanical or "fountain effect". If a capillary tube is placed into a bath of superfluid helium and then heated, even by shining a light on it, the superfluid helium will flow up through the tube and out the top as a result of the Clausius-Clapeyron relation. A second unusual effect is that superfluid helium can form a layer, a single atom thick, up the sides of any container in which it is placed. Viscosity is a measure of the resistance of a fluid to deform under shear stress. ... Ice melting - classic example of entropy increasing[1] described in 1862 by Rudolf Clausius as an increase in the disgregation of the molecules of the body of ice. ... In physics, thermal conductivity, k, is the intensive property of a material that indicates its ability to conduct heat. ... The temperature gradient in a given direction from a given spatial starting point is the rate at which temperature changes relative to distance in that direction from that point. ... International safety symbol Caution, risk of electric shock (ISO 3864), colloquially known as high voltage symbol. ... Superconductivity is a phenomenon occurring in certain materials at low temperatures, characterised by the complete absence of electrical resistance and the damping of the interior magnetic field (the Meissner effect. ... Capillary action or capillarity is the ability of a narrow tube to draw a liquid upwards against the force of gravity. ... This article does not cite any references or sources. ... The Clausius-Clapeyron relation, in thermodynamics, is a way of characterizing the phase transition between two states of matter, such as solid and liquid. ...

A more fundamental property than the disappearance of viscosity becomes visible if superfluid is placed in a rotating container. Instead of rotating uniformly with the container, the rotating state consists of quantized vortices. That is, when the container is rotated at speed below the first critical velocity (related to the quantum numbers for the element in question) the liquid remains perfectly stationary. Once the first critical velocity is reached, the superfluid will very quickly begin spinning at the critical speed. The speed is quantized - i.e. it can only spin at certain speeds. A quantum vortex is a topological defect exhibited in superfluids and superconductors. ... This article does not cite any references or sources. ... In physics, velocity is defined as the rate of change of displacement or the rate of displacement. ... A quantum number is a number used to parametrise certain properties of particles or other systems in quantum mechanics. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is defined by its atomic number; that is, by the number of protons in its nucleus. ...

Applications

Recently in the field of chemistry, superfluid helium-4 has been successfully used in spectroscopic techniques, as a quantum solvent. Referred to as Superfluid Helium Droplet Spectroscopy (SHeDS), it is of great interest in studies of gas molecules, as a single molecule solvated in a superfluid medium allows a molecule to have effective rotational freedom - allowing it to behave exactly as it would in the "gas" phase. For other uses, see Chemistry (disambiguation). ... Spectroscopy is the study of spectra, ie. ... Any superfluid can theoretically act as a quantum solvent. ... This article does not cite any references or sources. ... 3D (left and center) and 2D (right) representations of the terpenoid molecule atisane. ...

Superfluids are also used in high-precision devices, such as gyroscopes, which allow the measurement of some theoretically predicted gravitational effects (for an example see the Gravity Probe B article). A gyroscope is a device which demonstrates the principle of conservation of angular momentum, in physics. ... Gravity Probe B with solar panels folded Gravity Probe B (GP-B) is a satellite-based mission which launched in 2004. ...

Recently, superfluids have been used to trap and slow the speed of light. In an experiment, performed by Lene Hau, light was passed through a superfluid and found to be slowed to 17 meters per second^[1] (normally 299,792,458 meters per second). “Lightspeed” redirects here. ... Lene Vestergaard Hau (born Vejle, Denmark November 13, 1959) is a Danish physicist. ...

The Infrared Astronomical Satellite (IRAS), launched in January 1983 to gather infrared data was cooled by 720 litres of superfluid helium, maintaining a temperature of 1.6K (-271.6 ­°C). For other uses, see Infrared (disambiguation). ... Astronomy, which etymologically means law of the stars, (from Greek: αστρονομία = άστρον + νόμος) is a science involving the observation and explanation of events occurring outside Earth and its atmosphere. ... For other uses, see Satellite (disambiguation). ... The Infrared Astronomical Satellite (IRAS) was a space-based observatory that performed a survey of the entire sky at infrared wavelengths. ... Year 1983 (MCMLXXXIII) was a common year starting on Saturday (link displays the 1983 Gregorian calendar). ... For other uses, see Data (disambiguation). ... For other uses, see Temperature (disambiguation). ...

Recent discoveries

Physicists have recently been able to create a Fermionic condensate from pairs of ultra-cold fermionic atoms. Under certain conditions, fermion pairs form diatomic molecules and undergo Bose–Einstein condensation. At the other limit, the fermions (most notably superconducting electrons) form Cooper pairs which also exhibit superfluidity. This recent work with ultra-cold atomic gases has allowed scientists to study the region in between these two extremes, known as the BEC-BCS crossover. Many famous physicists of the 20th and 21st century are found on the list of recipients of the Nobel Prize in physics. ... A computer rendering of the Nitrogen Molecule, which is a diatomic molecule. ... A Bose–Einstein condensate (BEC) is a state of matter formed by a system of bosons confined in an external potential and cooled to temperatures very near to absolute zero (0 kelvin or −273. ... BCS theory successfully explains conventional superconductivity, the ability of certain metals at low temperatures to conduct electricity without resistance. ... For a List of scientists, see: List of anthropologists List of astronomers List of biologists List of chemists List of computer scientists List of economists List of engineers List of geologists List of inventors List of mathematicians List of meteorologists List of physicists Scientist pairs List of scientist pairs See...

Additionally, supersolids might have also been discovered, in 2004, by physicists at Penn State University. When helium-4 is cooled, below about 200 mK under high pressures, a fraction (~1%) of the solid appears to become superfluid [1]. Phase diagram for 4He A supersolid is a spatially ordered superfluid. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... The Pennsylvania State University The Pennsylvania State University (commonly known as Penn State) is a state-related land-grant university in Pennsylvania, with over 80,000 students at 24 campuses throughout the state. ... In common usage a fraction is any part of a unit. ... For other uses, see Solid (disambiguation). ...

Books

• Hagen Kleinert, Gauge Fields in Condensed Matter, Vol. I, "SUPERFLOW AND VORTEX LINES", pp. 1–742, World Scientific (Singapore, 1989); Paperback ISBN 9971-5-0210-0 (also available online here)

Hagen Kleinert, Photo taken in 2006 Hagen Kleinert is Professor of Theoretical Physics at the Free University of Berlin, Germany, and Honorary Member of the Russian Academy of Creative Endeavors. ...

See also

• Superdiamagnetism
• Bose-Einstein condensate
• Superconductivity
• Quantum vortex
• Supersolid
• superfluid film
• Douglas D. Osheroff

Superdiamagnetism (or perfect diamagnetism) is a phenomenon occurring in certain materials at low temperatures, characterised by the complete absence of magnetic susceptibility and the exclusion of the interior magnetic field. ... A Bose–Einstein condensate is a phase of matter formed by bosons cooled to temperatures very near to absolute zero (0 kelvins or -273. ... A magnet levitating above a high-temperature superconductor, cooled with liquid nitrogen. ... A quantum vortex is a topological defect exhibited in superfluids and superconductors. ... Phase diagram for 4He A supersolid is a spatially ordered superfluid. ... // Superfluidity and Superconductivity are of inherent interest because they are macroscopic manifestations of quantum mechanics. ... Douglas Dean Osheroff (born August 1, 1945) is a American physicist. ...

References

External links

• Superfluid phases of helium
• Lancaster University, Ultra Low Temperature Physics - Superfluid helium-3 research group.
• http://www.aip.org/png/html/helium3.htm
• http://www.aip.org/pt/vol-54/iss-2/p31.html
• http://web.mit.edu/newsoffice/2005/matter.html
• http://physicsweb.org/articles/world/11/6/3/1

In the physical sciences, a state of matter is one of the many ways that matter can interact with itself to form a macroscopic, homogenous phase. ... This is a list of the different states of matter including the more exotic ones (see phases of matter). ... For other uses, see Solid (disambiguation). ... A liquid will usually assume the shape of its container A liquid is one of the main states of matter. ... This article does not cite any references or sources. ... For other uses, see Plasma. ... In general, a colloid or colloidal dispersion is a substance with components of one or two phases, a type of mixture intermediate between a homogeneous mixture (also called a solution) and a heterogeneous mixture with properties also intermediate between the two. ... A supercritical fluid is any substance at a temperature and pressure above its thermodynamic critical point. ... Phase diagram for 4He A supersolid is a spatially ordered superfluid. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... A QGP is formed at the collision point of two relativistically accelerated gold ions in the center of the STAR detector at the relativistic heavy ion collider at the Brookhaven national laboratory. ... This article or section is in need of attention from an expert on the subject. ... A Bose–Einstein condensate (BEC) is a state of matter formed by a system of bosons confined in an external potential and cooled to temperatures very near to absolute zero (0 kelvin or −273. ... This article is considered orphaned, since there are very few or no other articles that link to this one. ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ... Italic text This article is about the boiling point of liquids. ... In physics, the triple point of a substance is the temperature and pressure at which three phases (gas, liquid, and solid) of that substance may coexist in thermodynamic equilibrium. ... In physical chemistry, thermodynamics, chemistry and condensed matter physics, a critical point, also called a critical state, specifies the conditions (temperature, pressure) at which the liquid state of the matter ceases to exist. ... In physics and thermodynamics, an equation of state is a relation between state variables. ... A cooling curve of naphthalene from liquid to solid. ...

References