Abstract :
The paper focuses on the theoretical studies regarding the correlation between the lattice structure, band structure, spin fluctuations, and T c in the iron-based superconductors. It is shown how the appearance and the disappearance of the pocket-like Fermi surfaces affect the spin fluctuations and superconductivity. Within the theoretical study described here, T c is optimized around the regular tetrahedron bond angle because the Fermi surface multiplicity tends to be maximized around that angle due to the good symmetry of the system. A possible guiding principle for obtaining higher T c materials is provided.
