Electronic structure of the superconducting layered non-cupra Sr₂RuO₄ from 2D-ACAR measurements

The three-dimensional electron density in momentum space ρ(P) and in wave vector space n(k) were constructed for Sr₂RuO₄. The measurements were achieved using 512 detectors to yield two dimensional angular correlation of annihilation radiation 2D-ACAR spectra, ρ(P) Spectra disclosed a d-like character that was interpreted via the electronic configuration of Ru. From another standpoint, the Fermi surface topology was compared to the theoretical band structure calculation based on the local density approximation (LDA). It clarified that two electron surfaces are running along the Γ-Z direction and one hole surface around the X point. It was noteworthy that, while Sr₂RuO₄ has a low critical temperature T_c, its Fermi surface is large and complex similar to that of a high-temperature superconductor (HTS).