ÖPG-CMD Joint Meeting 2026

P004 - Extension of the iterated perturbation theory for arbitrary fillings to nonequilibrium steady states

Sep 21, 2026, 1:30 PM

1h

RESOWI B+F (University of Graz)

1) Poster M03 - Correlated Materials Out of Equilibrium Poster session

Speaker

Tommaso Maria Mazzocchi (Graz University of Technology)

Description

I will present ongoing work on the extension of the iterated perturbation theory (IPT) impurity solver for arbitrary fillings to nonequilibrium steady-state problems. By merging the generalized IPT for arbitrary fillings proposed in Ref. [1] with the nonequilibrium Keldysh Green's function formalism [2], we extend the Ansatz for the electronic self-energy, in particular its Keldysh component. I will first show some equilibrium benchmarks and then address the nonequilibrium electron transport across a correlated impurity for selected fillings, temperatures and interaction strengths. The extended IPT is benchmarked against the auxiliary master equations approach (AMEA) impurity solver and shows overall good agreement in the regions where AMEA is reliable. This suggests that this extended IPT can be used as an approximate scheme to tackle nonequilibrium impurity problems and calls for a thorough investigation of other systems and observables, possibly within dynamical mean-field theory.

[1] Kajueter et al., Phys. Rev. Lett. 77, 131 (1996)
[2] Keldysh, Sov. Phys. JETP 20, 1018 (1965)