We report on results of realistic electronic structure calculations of the Pu-based ${\mathrm{PuCoGa}}_5$ superconductor based on the dynamical mean field theory. We find that dynamical correlations due to the local Coulomb interaction between Pu $f$ electrons lead to a substantial modification of the electronic structure with a narrow peak being formed in the vicinity of $E_F$, in agreement with the experimental photoemission spectra, and in contrast to the recent calculations within the $\mathrm{LDA}+\mathrm{U}$ method in Shick et al. [Phys. Rev. Lett. 94, 016401 (2005)], where only static electronic correlations have been included. Both Pu and Co contribute in equal footing to the narrow peak on the density of states at the Fermi level, the Co partial density of states being prominently affected by electronic correlations on the Pu sites. The $\mathbf{k}$-resolved spectral density is calculated and the theoretical spectral function resolved extended Van Hove singularity near $E_F$. This singularity may lead to enchancement of the magnetic susceptibility and favor $d$-wave superconductivity.

• Received 13 January 2006

DOI:https://doi.org/10.1103/PhysRevB.73.060506