Matches in DBpedia 2014 for { <http://dbpedia.org/resource/Flux_pumping> ?p ?o. }
Showing items 1 to 21 of
21
with 100 items per page.
- Flux_pumping abstract "Flux pumping is a method for magnetising bulk superconductors to fields in excess of 15 teslas. The method can be applied to any type II superconductor and exploits a fundamental property of superconductors. That is their ability to support and maintain currents on the length scale of the superconductor. Conventional magnetic materials are magnetised on a molecular scale which means that superconductors can maintain a flux density orders of magnitude bigger than conventional materials. Flux pumping is especially significant when one bears in mind that all other methods of magnetising superconductors require application of a magnetic flux density at least as high as the final required field. This is not true of flux pumping.An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source. In a normal conductor, an electrical current may be visualized as a fluid of electrons moving across a heavy ionic lattice. The electrons are constantly colliding with the ions in the lattice, and during each collision some of the energy carried by the current is absorbed by the lattice and converted into heat, which is essentially the vibrational kinetic energy of the lattice ions. As a result, the energy carried by the current is constantly being dissipated. This is the phenomenon of electrical resistance.The situation is different in a superconductor. In a conventional superconductor, the electronic fluid cannot be resolved into individual electrons. Instead, it consists of bound pairs of electrons known as Cooper pairs. This pairing is caused by an attractive force between electrons from the exchange of phonons. Due to quantum mechanics, the energy spectrum of this Cooper pair fluid possesses an energy gap, meaning there is a minimum amount of energy ΔE that must be supplied in order to excite the fluid. Therefore, if ΔE is larger than the thermal energy of the lattice, given by kT, where k is Boltzmann's constant and T is the temperature, the fluid will not be scattered by the lattice. The Cooper pair fluid is thus a superfluid, meaning it can flow without energy dissipation.In a class of superconductors known as type II superconductors, including all known high-temperature superconductors, an extremely small amount of resistivity appears at temperatures not too far below the nominal superconducting transition when an electrical current is applied in conjunction with a strong magnetic field, which may be caused by the electrical current. This is due to the motion of vortices in the electronic superfluid, which dissipates some of the energy carried by the current. If the current is sufficiently small, the vortices are stationary, and the resistivity vanishes. The resistance due to this effect is tiny compared with that of non-superconducting materials, but must be taken into account in sensitive experiments.".
- Flux_pumping wikiPageExternalLink CoombsT_2LPB01.pdf.
- Flux_pumping wikiPageExternalLink default.aspx.
- Flux_pumping wikiPageExternalLink sust8_3_034001.pdf?request-id=c7d7bb8e-5d5d-4cfb-ba5c-f4780fcdde40.
- Flux_pumping wikiPageExternalLink contents1.html.
- Flux_pumping wikiPageExternalLink science?_ob=ArticleURL&_udi=B6TVJ-4R5VYVP-3&_user=10&_coverDate=02%2F01%2F2008&_alid=949433122&_rdoc=1&_fmt=high&_orig=search&_cdi=5536&_sort=r&_docanchor=&view=c&_ct=1&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=bbd2a42db980cdb05f2a25add9f2ecb8.
- Flux_pumping wikiPageExternalLink search?q=%22flux+pumping%22+superconducting&t=all&sort=0&g=s.
- Flux_pumping wikiPageExternalLink 0356.htm.
- Flux_pumping wikiPageID "23355682".
- Flux_pumping wikiPageRevisionID "605584183".
- Flux_pumping hasPhotoCollection Flux_pumping.
- Flux_pumping subject Category:Levitation.
- Flux_pumping subject Category:Spintronics.
- Flux_pumping subject Category:Superconductivity.
- Flux_pumping comment "Flux pumping is a method for magnetising bulk superconductors to fields in excess of 15 teslas. The method can be applied to any type II superconductor and exploits a fundamental property of superconductors. That is their ability to support and maintain currents on the length scale of the superconductor. Conventional magnetic materials are magnetised on a molecular scale which means that superconductors can maintain a flux density orders of magnitude bigger than conventional materials.".
- Flux_pumping label "Flux pumping".
- Flux_pumping sameAs m.06wbpxz.
- Flux_pumping sameAs Q5463030.
- Flux_pumping sameAs Q5463030.
- Flux_pumping wasDerivedFrom Flux_pumping?oldid=605584183.
- Flux_pumping isPrimaryTopicOf Flux_pumping.