High-resolution angle-resolved photoemission spectroscopy has been carried out on a ruthenate superconductor Sr2RuO4 (Tc ∼ 1 K), which has the same crystal structure as La2CuO4, but with RuO2 layers replacing the CuO2, and exhibits T2 dependence of electrical resistivity below 25 K. The results show that the electronic structure of Sr2RuO4 has an extended van-Hove singularity (VHS) near EF in a quite similar manner to the high Tc cuprates, regardless of the character of the electronic states near EF. This requests reexamination of the VHS scenario and its relation to both the normal and superconducting properties.
|Number of pages||4|
|Journal||Journal of Electron Spectroscopy and Related Phenomena|
|Publication status||Published - 1996 May|