To understand the recently established unique magnetic and superconducting phase diagram of LaFeAsO1-xHx, we analyze the realistic multiorbital tight-binding model for x=0-0.4 beyond the rigid-band approximation. Both the spin and orbital susceptibilities are calculated in the presence of the Coulomb and charge quadrupole interactions. It is found that both orbital and spin fluctuations strongly develop at both x∼0 and 0.4, due to the strong violation of the rigid-band picture in LaFeAsO 1-xHx. Based on this result, we discuss the experimental phase diagram, especially the double-dome superconducting phase. Moreover, we show that the quadrupole interaction is effectively produced by the vertex correction due to Coulomb interaction, resulting in the mutual development of spin and orbital fluctuations.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Jul 22 2013|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics