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arXiv · 0908.0681

Krylov implementation of the hybridization expansion impurity solver and application to 5-orbital models

Andreas Laeuchli·Philipp Werner
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Abstract

We present an implementation of the hybridization expansion impurity solver which employs sparse matrix exact-diagonalization techniques to compute the time evolution of the local Hamiltonian. This method avoids computationally expensive matrix-matrix multiplications and becomes advantageous over the conventional implementation for models with 5 or more orbitals. In particular, this method will allow the systematic investigation of 7-orbital systems (lanthanide and actinide compounds) within single-site dynamical mean field theory. We illustrate the power and usefulness of our approach with dynamical mean field results for a 5-orbital model which captures some aspects of the physics of the iron based superconductors.

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Andreas Laeuchli, Philipp Werner. 2009-12-12. Krylov implementation of the hybridization expansion impurity solver and application to 5-orbital models. https://doi.org/10.1103/physrevb.80.235117

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