SUPERconductors
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O n t h e T r a c k o f M o d e r n P h y s i c s and Leonardo da Vinci, EU “Supercomet2” network 1913 "for his investigations on the properties of m atter at low tem peratures w hich led, inter alia, to the production of liquid helium " H eike K am erlin g h O nnes 1962 "for his pioneering theories for condensed m atter, especially liquid helium " Lev D avidovich Landau 1972 "for their jointly developed theory of superconductivity, usually called the B C S -theory" John B ardeen / Leon N eil C o o p er/ John R o b ert S ch rieffer 1973 "for their experim entaldiscoveries regarding tunneling phenom ena in sem iconductors and superconductors, respectively" for his theoreticalpredictions of the properties of a supercurrent through a tunnelbarrier, in particular those phenom ena w hich are generally know n as the Josephson effects" Leo Esaki/ Ivar G iaever B rian / D a vid Josephson 1987 "for their im portant break-through in the discovery of superconductivity in ceram ic m aterials" J. G eorg B ednorz /K . A lexander M üller 2003 "for pioneering contributions to the theory of superconductors and superfluids" A lexeiA . A brikosov/ V italy L. G in zb u rg / A n th o n y J. Leg g ett If you want a Super Prize you should think of SUPERconductivity Floating Sumo Wrestler Normal SQUID [1] Maglev Demonstration Line - from Pudong International Airport to Longyang Road Metro Station - the 30- kilometer trip will take only eight minutes. It is the world's first commercial magnetic levitation line. From March 29 2004, it was put into use formally and operates everyday from 8:30am to 17:30pm. The operation interval is 20 minutes. The round trip ticket cost 80 yuan and the one way ticket cost 50 yuan. Passengers with current day flight ticket can buy a one way ticket of Maglev Train at 20% discount. Add: Maglev Train Station of Longyang Rd Price(RMB): One Way Ticket:50, 100(VIP) Round Trip Ticket:80, 160(VIP) Tel:28907777 [1] Superconducting QUantum Interference Device A direct current SQUID, consists of two Josephson junctions employed in parallel so that electrons tunneling through the junctions demonstrate quantum interference, dependent upon the strength of the magnetic field within a loop. text: http://whatis.techtarget.com/definition/0,,sid9_gci816722,00.html photo: http://krissol.kriss.re.kr/quantum/supercon/squid.html: see Superconducting materials: •about 30 elements are known (table A) •As, Be, Cs, Ge, Si and Te are only superconducting •oxide superconductors are a sort of ceramics (table B) Non-superconducting materials: •normally good conductors e. g. Cu and Ag are not •magnetic materials e.g. Fe or Ni are not •transition elements are not Bardeen, Copper and Schrieffer waited 25 years to get the Nobel prize for explaining the superconductivity in metals. Immediately after, new superconductors were discovered, in “strange” materials, with complex crystalline lattices. We have no explanation for SC in copper oxides, at present. If you want a Super Prize you should think of SUPERconductivity! A surprising discovery came in 2001: crystallographically simple MgB 2 becomes superconductive at 39 K. Also lithium becomes superconducting, at high (48 GPa) pressure. Scientists do not exclude that even hydrogen, at high pressures, in metallic phase can be superconducting. Discovery of materials with successively higher Tc’s over the last century. (Points circled in red garnered a Nobel Prize for their discoverers: Kamerlinbh - Onnes in 1913 and Bednorz & Muller in 1987.) http://hoffman.physics.harvard.edu/ research/Scmaterials.php A m odelof Cooper pair attraction A passing electron attracts the lattice, causing a slight ripple toward its path Another electron passing in the opposite direction is attracted to that displacement Superconductivity is a kind of Bose-Einstein condensation. Unfortunately, only bosons, i.e. particles with the spin=1 (integer, in general) can condensate. Electrons are fermions, with spin =1/2. But if two electrons could couple, they would form a boson! The crystal matrix serves as a deformable mattress for this. [http://hyperphysics.phy- astr.gsu.edu/hbase/hframe.html] A B Yttrium barium copper oxide, or YBCO, chemical formula YBa 2 Cu 3 O 7 -, is a high -T (94 K) superconductor. Discovered by C.W. Chu in 1987 launched the era of high- temperature superconductors - it was the first material to break the liquid nitrogen (77 K) barrier.
description
SUPERman. SUPER SENSITIVE SQUID. Floating Sumo Wrestler. Normal SQUID [1]. - PowerPoint PPT Presentation
Transcript of SUPERconductors
O n t h e T r a c k o f M o d e r n P h y s i c sand Leonardo da Vinci, EU “Supercomet2” network
1913 "for his investigations on theproperties of matter at lowtemperatures which led, inter alia, tothe production of liquid helium"
Heike Kamerlingh Onnes
1962 "for his pioneering theories forcondensed matter, especially liquidhelium"
Lev Davidovich Landau
1972 "for their jointly developed theory ofsuperconductivity, usually called theBCS-theory"
J ohn Bardeen / Leon Neil Cooper/
J ohn Robert Schrieffer
1973 "for their experimental discoveriesregarding tunneling phenomena insemiconductors andsuperconductors, respectively" forhis theoretical predictions of theproperties of a supercurrent througha tunnel barrier, in particular thosephenomena which are generallyknown as the J osephson effects"
Leo Esaki / I var Giaever Brian/ DavidJ osephson
1987 "for their important break-through inthe discovery of superconductivity inceramic materials"
J . Georg Bednorz / K. Alexander
Müller
2003 "for pioneering contributions to thetheory of superconductors andsuperfluids"
Alexei A. Abrikosov/ Vitaly L.Ginzburg/ Anthony J . Leggett
If you want a Super Prize you should think of SUPERconductivity
Floating Sumo
Wrestler
Normal SQUID [1]
Maglev Demonstration Line - from Pudong International Airport to Longyang Road Metro Station - the 30-kilometer trip will take only eight minutes.It is the world's first commercial magnetic levitation line. From March 29 2004, it was put into use formally and operates everyday from 8:30am to 17:30pm. The operation interval is 20 minutes.
The round trip ticket cost 80 yuan and the one way ticket cost 50 yuan. Passengers with current day flight ticket can buy a one way ticket of Maglev Train at 20% discount. Add: Maglev Train Station of Longyang Rd
Price(RMB): One Way Ticket:50, 100(VIP)Round Trip Ticket:80, 160(VIP) Tel:28907777
[1] Superconducting QUantum Interference Device A direct current SQUID, consists of two Josephson junctions employed in parallel so that electrons tunneling through the junctions demonstrate quantum interference, dependent upon the strength of the magnetic field within a loop.
text: http://whatis.techtarget.com/definition/0,,sid9_gci816722,00.htmlphoto: http://krissol.kriss.re.kr/quantum/supercon/squid.html: see also: http://superconductors.org/
Superconducting materials:•about 30 elements are known (table A) •As, Be, Cs, Ge, Si and Te are only superconducting•oxide superconductors are a sort of ceramics (table B)
Non-superconducting materials:•normally good conductors e. g. Cu and Ag are not •magnetic materials e.g. Fe or Ni are not•transition elements are not
Bardeen, Copper and Schrieffer waited 25 years to get the Nobel prize for explaining the superconductivity in metals. Immediately after, new superconductors were discovered, in “strange” materials, with complex crystalline lattices. We have no explanation for SC in copper oxides, at present.
If you want a Super Prize you should think of SUPERconductivity!
http://www.simplicatus.no/web.php?action=homepage_view_single&pk=25
A surprising discovery came in 2001: crystallographically simple MgB2 becomes superconductive at 39 K. Also lithium becomes superconducting, at high (48 GPa) pressure. Scientists do not exclude that even hydrogen, at high pressures, in metallic phase can be superconducting.
Discovery of materials with successively higher Tc’s over the last century. (Points circled in red garnered a Nobel Prize for their discoverers: Kamerlinbh - Onnes in 1913 and Bednorz & Muller in 1987.)
http://hoffman.physics.harvard.edu/research/Scmaterials.php
A model of Cooper pair attraction A passing electron
attracts the lattice, causing a slight ripple toward its path
Another electron passing in the opposite direction is attracted to that displacement
Superconductivity is a kind of Bose-Einstein condensation. Unfortunately,only bosons, i.e. particles with the spin=1 (integer, in general) cancondensate. Electrons are fermions, with spin =1/2. But if two electrons could couple, they would form a boson! The crystal matrix serves as a deformable mattress for this.
[http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html]
A
B
Yttrium barium copper oxide, or YBCO, chemical formula YBa2Cu3O7-, is a high -T (94 K) superconductor. Discovered by C.W. Chu in 1987 launched the era of high- temperature superconductors - it was the first material to break the liquid nitrogen (77 K) barrier.
