Fluorine effect in layered oxypnictide LaOFeAs

TL;DR

This study uses theoretical calculations to explore how fluorine doping affects the electronic structure of LaOFeAs, revealing changes in Fe d-orbitals that may influence superconductivity, similar to phenomena observed in cuprate superconductors.

Contribution

It provides a detailed analysis of fluorine's impact on Fe d-orbitals in LaOFeAs, highlighting orbital symmetry changes related to superconductivity.

Findings

Fluorine doping alters Fe d-orbital symmetry from dz2 to dx2-y2.

Orbital changes suggest increased conductivity with fluorine doping.

Results align with behaviors seen in high-temperature copper-based superconductors.

Abstract

Theoretical calculations under the scheme of WIEN2k computer package had been performed on the pristine compound LaOFeAs, as well as on LaO1-xFxFeAs. One factor crucial to the manifestation of superconductivity seems to be fluorine doping; hence we search for its effect. Paying close attention to Fe d-orbitals upon doping of F by O, at first, Fe d-orbitals have dz2 symmetry, changing gradually to something akin to dx2-y2 which seems more prone to conductivity than the former one. This issue agree with the accepted results happened in the copper-based high-temperature superconductors.