Magnetism and Fermi surfaces of UGe2

A self-consistent calculation of the ground-state electronic structure and magnetic properties of the ferromagnetic superconductor UGe2 is performed using a Dirac-type relativistic spin-polarized linearized augmented-plane-wave (LAPW) method within a local spin-density approximation. The total energy oriented along the (100) direction of magnetization gives a minimum compared with the other directions, in agreement with the fact that the easy axis is along the (100) direction. In addition, the orbital moment is comparable to recent neutron scattering measurements. The ferromagnetic Fermi surfaces are composed mainly of the 5f-majority spin state with some nesting structures