Angle-resolved photoemission spectroscopy was performed on a ruthenate superconductor Sr2RuO4(Tc∼1 K) which has the same crystal structure as La2CuO4, but with RuO2 layers replacing CuO2 layers. Sr2RuO4 shows an extended Van Hove singularity (VHS) at 20±2 meV below EF just like the cuprates, regardless of the character of the electronic states at EF. This suggests that the extended VHS is a general feature of a two-dimensional correlated d-electron metal. The observed Fermi surface is in contrast to local-density-approximation calculations.
ASJC Scopus subject areas
- Physics and Astronomy(all)