News tagged with superconductors
High-temperature superconductor spills secret: A new phase of matter
(PhysOrg.com) -- Scientists from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley have joined with researchers at Stanford University ...
Mar 24, 2011 |
4.7 / 5 (42) |
18
|
Physicists use offshoot of string theory to describe puzzling behavior of superconductors
(PhysOrg.com) -- Physicists are divided on whether string theory is a viable theory of everything, but many agree that it offers a new way to look at physical phenomena that have otherwise proven difficult ...
Aug 05, 2010 |
4.6 / 5 (39) |
143
|
Physicists explain why superconductors fail to produce super currents
When high-temperature superconductors were first announced in the late 1980s, it was thought that they would lead to ultra-efficient magnetic trains and other paradigm-shifting technologies.
Jun 27, 2010 |
4.7 / 5 (35) |
19
|
Fahrenheit -459: Neutron stars and string theory in a lab
(PhysOrg.com) -- Using lasers to contain some ultra-chilled atoms, a team of scientists has measured the viscosity or stickiness of a gas often considered to be the sixth state of matter. The measurements ...
Dec 09, 2010 |
4.8 / 5 (32) |
8
|
Physicists unveil unexpected properties in superconducting material
In 2008, an international team of scientists studying an exotic new superconductor based on the element ytterbium reported that it displays unusual properties that could change how scientists understand and ...
Jan 20, 2011 |
5 / 5 (30) |
0
|
Superconductor breakthrough could power new advances (w/ Video)
(PhysOrg.com) -- The first batch of a new range of powerful superconductors which could revolutionise the production of machines like hospital MRI scanners and protect the national grid has been developed ...
Jul 09, 2010 |
4.6 / 5 (31) |
26
|
LHC now colder than deep space
(PhysOrg.com) -- The LHC (Large Hadron Collider) is once again colder than deep space as it is prepared for experiments to resume in late November.
Oct 20, 2009 |
4.6 / 5 (28) |
7
Hot booze turns material into a superconductor
(PhysOrg.com) -- A Japanese scientist who "likes alcohol very much" has discovered that soaking samples of material in hot party drinks for 24 hours turns them into superconductors at ambient temperature.
Jan 11, 2011 |
2.2 / 5 (58) |
28
|
Chandra finds superfluid in neutron star's core
(PhysOrg.com) -- NASA's Chandra X-ray Observatory has discovered the first direct evidence for a superfluid, a bizarre, friction-free state of matter, at the core of a neutron star. Superfluids created in ...
Feb 23, 2011 |
4.7 / 5 (27) |
32
|
Roller coaster superconductivity discovered
Superconductors are more than 150 times more efficient at carrying electricity than copper wires. However, to attain the superconducting state, these materials have to be cooled below an extremely low, so-called ...
Aug 18, 2010 |
4.7 / 5 (26) |
30
|
Light touch transforms material into a superconductor
(PhysOrg.com) -- A non-superconducting material has been transformed into a superconductor using light, Oxford University researchers report.
Jan 14, 2011 |
4.9 / 5 (25) |
9
|
Researchers find possible evidence of Majorana fermions
(Phys.org) -- Researchers working out of Delft University of Technology in the Netherlands have constructed a device that appears to offer some evidence of the existence of Majorana fermions; the elusive particles ...
Apr 13, 2012 |
4.8 / 5 (25) |
4
|
Quantum fractals at the border of magnetism
U.S., German and Austrian physicists studying the perplexing class of materials that includes high-temperature superconductors are reporting this week the unexpected discovery of a simple "scaling" behavior in the electronic ...
Jul 29, 2010 |
4.9 / 5 (23) |
5
|
Electron's negativity cut in half by supercomputer
(PhysOrg.com) -- While physicists at the Large Hadron Collider smash together thousands of protons and other particles to see what matter is made of, they're never going to hurl electrons at each other. No ...
Jan 12, 2012 |
4.2 / 5 (26) |
36
|
Innovative superconductor fibers carry 40 times more electricity
Wiring systems powered by highly-efficient superconductors have long been a dream of science, but researchers have faced such practical challenges such as finding pliable and cost-effective materials. Now ...
Sep 07, 2011 |
4.6 / 5 (23) |
23
|
Superconductivity
Superconductivity is a phenomenon occurring in certain materials generally at very low temperatures, characterized by exactly zero electrical resistance and the exclusion of the interior magnetic field (the Meissner effect). It was discovered by Heike Kamerlingh Onnes in 1911. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It cannot be understood simply as the idealization of "perfect conductivity" in classical physics.
The electrical resistivity of a metallic conductor decreases gradually as the temperature is lowered. However, in ordinary conductors such as copper and silver, impurities and other defects impose a lower limit. Even near absolute zero a real sample of copper shows a non-zero resistance. The resistance of a superconductor, despite these imperfections, drops abruptly to zero when the material is cooled below its "critical temperature". An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source.
Superconductivity occurs in a wide variety of materials, including simple elements like tin and aluminium, various metallic alloys and some heavily-doped semiconductors. Superconductivity does not occur in noble metals like gold and silver, nor in pure samples of ferromagnetic metals.
In 1986 the discovery of a family of cuprate-perovskite ceramic materials known as high-temperature superconductors, with critical temperatures in excess of 90 kelvin, spurred renewed interest and research in superconductivity for several reasons. As a topic of pure research, these materials represented a new phenomenon not explained by the current theory. In addition, because the superconducting state persists up to more manageable temperatures, past the economically-important boiling point of liquid nitrogen (77 kelvin), more commercial applications are feasible, especially if materials with even higher critical temperatures could be discovered.
See also the history of superconductivity.
For more information about Superconductivity, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
