Quasiparticle structure of Sr₂RuO_4.

The non-copper layered perovskite, Sr2RuO4, is expected to be a very useful reference material for interpreting experiments on the high Tc. cuprate superconductors. A band structure calculation for Sr2RuO4 is performed. Starting from the electronic structure determined in the local density formalism, the Dyson's equation with self-energies arising from the Hubbard hamiltonian is solved by diagonalizing the Green's function in k-space. The density of states is obtained by considering the renormalization factor and the life-times of the quasiparticle states in each pole of the interacting system. This leads to modification of the density of states calculated in the local density formalism, and the results fit experimental data not only in the position of peaks, but also in their intensity and in the number of states at Fermi level. © 1999 Elsevier Science B.V. All rights reserved.