Spin and charge susceptibilities of the two-orbital model within the cluster perturbation theory for Fe-based materials

S. V. Nikolaev; M. M. Korshunov

doi:10.1007/s10948-016-3784-8

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arXiv · 1607.08861

Spin and charge susceptibilities of the two-orbital model within the cluster perturbation theory for Fe-based materials

S. V. Nikolaev·M. M. Korshunov

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Abstract

Cluster perturbation theory is used to calculate band structure, spectral functions, Fermi surface, and spin and charge susceptibilities for the two-orbital model of iron pnictides with the on-site multiorbital Hubbard interactions. Susceptibilities are calculated within the approximation combining the cluster perturbation theory for the self-energy corrections and the random-phase approximation (RPA) for the vertex renormalizations. Calculations for the small values of Hubbard repulsion $U \leq 2$ confirm that the rigid band approximation and RPA for the spin and charge susceptibilities are suitable approaches for the case of weak interactions.

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S. V. Nikolaev, M. M. Korshunov. 2016-07-29. Spin and charge susceptibilities of the two-orbital model within the cluster perturbation theory for Fe-based materials. https://doi.org/10.1007/s10948-016-3784-8

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