High-temperature superconductivity
hideHigh-temperature superconductors (abbreviated high-Tc or HTS) are materials that have a superconducting transition temperature (Tc) above 30 K, which was thought (1960-1980) to be the highest theoretically allowed Tc. The first high-Tc superconductor was discovered in 1986 by Karl Müller and Johannes Bednorz, for which they were awarded the Nobel Prize in Physics in 1987. The term high-temperature superconductor was used interchangeably with cuprate superconductor until Fe-based superconductors were discovered in 2008. The best known high-temperature superconductors are bismuth strontium calcium copper oxide, BSCCO and yttrium barium copper oxide, YBCO.
High-temperature has three common definitions in the context of superconductivity:
Technological applications benefit from both the higher critical temperature being above the boiling point of liquid nitrogen and also the higher critical magnetic field (and critical current density) at which superconductivity is destroyed. In magnet applications the high critical magnetic field may be more valuable than the high Tc itself. Some cuprates have an upper critical field around 100 tesla. However, cuprate materials are brittle ceramics which are expensive to manufacture and not easily turned into wires or other useful shapes.
Two decades of intense experimental and theoretical research, with over 100,000 published papers on the subject, has discovered many common features in the properties of high-temperature superconductors, but as of 2009[update] there is no widely accepted theory to explain their properties. Cuprate superconductors (and other unconventional superconductors) differ in many important ways from conventional superconductors, such as elemental mercury or lead, which are adequately explained by the BCS theory. There also has been much debate as to high-temperature superconductivity coexisting with magnetic ordering in YBCO, iron-based superconductors, several ruthenocuprates and other exotic superconductors, and the search continues for other families of materials. HTS are Type-II superconductors which allow magnetic fields to penetrate their interior in quantized units of flux, meaning that much higher magnetic fields are required to suppress superconductivity. Their layered structure also affects their response to magnetic fields.
For more information about High-temperature superconductivity, read the full article at
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News tagged with high temperature superconductors
Race for Superconductors Shrinks to Nanoscale
Oct 09, 2009 |
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(PhysOrg.com) -- A team of researchers from UT Dallas, Clemson University and Yale University are using science on the nanoscale to address one of the most elusive challenges in physics - the discovery of ...
Rice researchers to build light-based crystal simulator
Sep 23, 2009 |
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A Rice University-led team of physicists at seven U.S. universities has won $5 million from the Department of Defense to build a simulator capable of tackling high-temperature superconductivity, one of the ...
Research pokes holes in Hubbard model: Could help solve enigma of high-temperature superconductors
Aug 19, 2009 |
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New UBC research has literally and figuratively poked holes in single-band Hubbard physics--a model that has been used to predict and calculate the behavior of high-temperature superconductors for 20 years.
Fire Meets Ice: Superhot And Supercold Remarkably Similar In The 'Fermion' World (w/ Video)
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Trapping and cooling a microscopic clump of gas and then suddenly releasing it would normally result in the gas rapidly expanding outward in all directions, like a spherical bubble.
New insights, and a new angle, on high-temperature superconductivity
Jun 29, 2009 |
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(PhysOrg.com) -- A Princeton-led research team has revealed surprising information about how electron behavior influences the conduction of electricity in a class of high-temperature superconductors. An increased ...
Magnetism Governs Properties of Iron-Based Superconductors
Mar 18, 2009 |
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(PhysOrg.com) -- Though a year has passed since the discovery of a new family of high-temperature superconductors, a viable explanation for the iron-based materials’ unusual talent remains elusive. But a team ...
Physicists offer new theory for iron compounds
Mar 12, 2009 |
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An international team of physicists from the United States and China this week offered a new theory to both explain and predict the complex quantum behavior of a new class of high-temperature superconductors.
Putting the Pressure on Iron-Based Superconductors
Mar 05, 2009 |
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(PhysOrg.com) -- Traditionally, magnetism and superconductivity don't mix. For more than 20 years, the only known superconductors that worked at so-called "high" temperatures (above 30 K, or about -406 degrees ...
Secrets behind high temperature superconductors revealed
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(PhysOrg.com) -- Scientists from Queen Mary, University of London and the University of Fribourg (Switzerland) have found evidence that magnetism is involved in the mechanism behind high temperature superconductivity.
