Are electronic correlations in the new iron-pnictide high-temperature superconductors as strong as in their older cuprate brethren? Yes, say some physicists; no, say others. X-ray experiments deliver the verdict.
Decoration experiments of the two-gap superconductor show evidence for long-range attraction between vortices in a superconducting mixed state, which is interpreted as coexisting type-I and type-II superconductivity.
After the discovery of superconductivity in doped sodium cobaltate, numerous measurements contributed to mapping out the various magnetic and electronic phases that occur in this material. Now, the report of a new phase diagram may challenge the previous version.
A new class of high-temperature superconductors has been discovered in layered iron arsenic compounds. Results in this rapidly moving field may shed light on the still unsolved problem of high-temperature cuprate superconductivity.
Physics1, 19 (2008) – Published September 15, 2008
Discovering superconductivity above room temperature is a dream for modern science and technology. Now, theorists propose that for certain types of superconductors, contact with a metal layer could greatly increase the transition temperatures of these materials—in some cases by as much as an order of magnitude.
The ability to tune the onset of superconductivity in a single crystal with other means than chemical doping makes the interpretation of results much cleaner. Now, scientists demonstrate pressure-induced superconductivity in undoped crystals of the pnictide CaFe2As2.
Phys. Rev. Focus21, 13 (2008) – Published April 17, 2008
Researchers used a magnetic material to create a difference in current-carrying properties between two perpendicular directions in a superconductor. They could easily change the directions with an external magnetic field, which could be useful in superconducting devices.
Phys. Rev. Focus18, 8 (2006) – Published September 11, 2006
Weaving together experimental clues and theoretical insights, three physicists devised in 1957 the first fundamental theory of superconductivity, one of the most successful theories in solid state physics.