2 research outputs found
A Twisted Ladder: relating the Fe superconductors to the high cuprates
We construct a 2-leg ladder model of an Fe-pnictide superconductor and
discuss its properties and relationship with the familiar 2-leg cuprate model.
Our results suggest that the underlying pairing mechanism for the Fe-pnictide
superconductors is similar to that for the cuprates.Comment: 5 pages, 4 figure
Electronic correlations in the iron pnictides
In correlated metals derived from Mott insulators, the motion of an electron
is impeded by Coulomb repulsion due to other electrons. This phenomenon causes
a substantial reduction in the electron's kinetic energy leading to remarkable
experimental manifestations in optical spectroscopy. The high-Tc
superconducting cuprates are perhaps the most studied examples of such
correlated metals. The occurrence of high-Tc superconductivity in the iron
pnictides puts a spotlight on the relevance of correlation effects in these
materials. Here we present an infrared and optical study on single crystals of
the iron pnictide superconductor LaFePO. We find clear evidence of electronic
correlations in metallic LaFePO with the kinetic energy of the electrons
reduced to half of that predicted by band theory of nearly free electrons.
Hallmarks of strong electronic many-body effects reported here are important
because the iron pnictides expose a new pathway towards a correlated electron
state that does not explicitly involve the Mott transition.Comment: 10 page