Observation of the coherent quasiparticle states in SrRu1–xIrxO3 films via polarization-dependent soft X-ray absorption spectroscopy

Abstract

The electronic structures of SrRu1-xIrxO3 films (0 <= x <= 1) have been investigated by employing polarization-dependent soft X-ray absorption spectroscopy. In SrIrO3, the coherent quasi-particle peak at the Fermi level (E-F) is clearly observed, reflecting the spin-orbit-coupled correlated metallic nature of SrIrO3. X-ray linear dichroism signals for x = 0 and x = 1 are negligibly weak, demonstrating the pseudo-cubic structure for SrRuO3 and the strong spin-orbit coupling in SrIrO3. In contrast, finite linear dichroism is observed for the intermediate x regime, indicating that the narrow d(xz) down arrow and d(yz) down arrow bands close to E-F are occupied less than the wide d(xy) down arrow band due to the enhanced in-plane hopping.