APS Logo

Novel subbands inelectronic spectral densities of correlated systems

ORAL

Abstract

In spite of important recent improvements in the theoretical handling of correlated materials, it is still difficult to obtain precise and detailed theoretical electronic structure results to compare with experiments.

We calculate and resolve with high precision the electronic spectral densities at zero temperature of one of the key models for multi-orbital strongly correlated electron materials, the Kanamori-Hubbard Hamiltonian (KH), by means of the Dynamical Mean Field Theory which uses the Density Matrix Renormalization Group (DMRG) as the (effective) impurity solver. Due to the precision of this technique, we are able to observe the existence of unforeseen subbands and structure in the local density of states for finite values of the inter-orbital coupling V, which we characterize by calculating specific response functions. 

I will also show very recent results on the electronic densities of states of a one-dimensional version of the KH model calculated with DMRG, for which we also find in-gap subbands for finite values of V.

We expect that the results presented here together with the possibility of calculating more precise spectral functions for models of correlated materials will stimulate a closer study of the details of experimental results and, hence, will contribute to unveil the complex and elusive microscopic behavior of strongly correlated materials. 

Publication: - Subbands in the doped two-orbital Kanamori-Hubbard model, K. Hallberg and Y. Núñez- Fernández, Phys. Rev. B 102, 245138 (2020). DOI: 10.1103/PhysRevB.102.245138<br>- Emergent low-energy bound states in the two-orbital Hubbard model, Y. Núñez- Fernández, G. Kotliar, and K. Hallberg, Phys. Rev. B (Rapid Comm.) 97, 121113(R) (2018)<br>- In-gap band in the one-dimensional two-orbital Kanamori-Hubbard model with inter-orbital Coulomb interaction. N. Aucar Boidi, H. Fernández García, Y. Núñez-Fernández, and K. Hallberg, submitted to PRR (2021)

Presenters

  • Karen Hallberg

    Inst Balseiro

Authors

  • Karen Hallberg

    Inst Balseiro

  • Nair S Aucar Boidi

    Inst Balseiro

  • Yuriel Núñez Fernández

    CEA-Grenoble, IRIG-PHELIQS

  • Gabriel Kotliar

    Rutgers University, New Brunswick