Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Superconductivity: Which one of these is not like the other?

15.07.2009
APS Physics this Week: Iron-based superconductors

Superconductivity appears to rely on very different mechanisms in two varieties of iron-based superconductors. The insight comes from research groups that are making bold statements about the correct description of superconductivity in iron-based compounds in two papers about to be published in journals of the American Physical Society.

The 2008 discovery of high-temperature superconductivity in iron-based compounds has led to a flood of research in the past year. As the literature mounts on these materials, which superconduct at temperatures as high as 55 K, two key questions are emerging: Is the origin of superconductivity in all of the iron-based compounds the same and are these materials similar to the copper oxide-based high-temperature superconductors (commonly known as cuprates), which physicists have studied for nearly twenty years but are still unable to explain with a complete theory?

These questions are addressed separately in two papers highlighted in the July 13 issue of Physics. A collaboration between scientists at Lawrence Berkeley National Lab, the SLAC National Accelerator Laboratory, Stanford University and institutions in Switzerland, China, Mexico and the Netherlands reports in Physical Review B x-ray experiments indicating that, in iron-based superconductors that contain arsenic or phosphorous (called 'iron pnictides'), the electrons that ultimately pair to form the superconducting state behave differently than those in the cuprates. More specifically, while the electrons in the cuprates are strongly correlated – meaning the energy of one electron is tied to the energy of the others – the electrons in the iron-pnictide superconductors behave more like those of a normal metal in which the electrons do not (to first approximation) interact.

In a paper appearing in Physical Review Letters, scientists at Princeton, UC Berkeley and Shanghai Jiao Tong University in China present the first photoemission measurements on an iron-based superconductor that contains tellurium, Fe1+xTe. They argue the origin of superconductivity in this type of iron compound, which belongs to a class of materials called the iron-chalcogenides, has a different origin than in the arsenic and phosphorous containing iron-pnictides. In fact, the measurements suggest that superconductivity in the iron-chalcogenides may be more similar to that of the cuprates.

The statements put forth in these two articles are likely to influence the direction taken by physicists who work on the theory of iron-based superconductors. See the Viewpoint article in the July 13 issue of APS Physics to learn more.

About APS Physics:

APS Physics (physics.aps.org) publishes expert written commentaries and highlights of papers appearing in the journals of the American Physical Society. Here are some of the papers that will be featured in the next issue of APS Physics.

James Riordon | EurekAlert!
Further information:
http://physics.aps.org

More articles from Physics and Astronomy:

nachricht NASA's SDO sees partial eclipse in space
29.05.2017 | NASA/Goddard Space Flight Center

nachricht Strathclyde-led research develops world's highest gain high-power laser amplifier
29.05.2017 | University of Strathclyde

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>