Electronic structure and magnetism of RbGd2Fe4As4O2

The electronic structure, magnetism, and Fermi surface (FS) nesting of new superconductor RbGd2Fe4As4O2 (12442) were studied by the first-principes calculation. Its calculated ground state is the stripe antiferromagnetic state. The hole-like FSs will overlap with the electron-like FS sheets by the electron doping. Such significant FS nesting induces a peak of the bare susceptibility χ0(q→) at the X point, suggesting the parent compound RbGd2Fe4As4O2 is a self hole-doping induced superconductor.