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arXiv · 1209.0915

Conserved quantities of SU(2)-invariant interactions for correlated fermions and the advantages for quantum Monte Carlo simulations

Nicolaus Parragh·Alessandro Toschi·Karsten Held·Giorgio Sangiovanni
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Abstract

In the context of realistic calculations for strongly-correlated materials with $d$- or $f$-electrons the efficient computation of multi-orbital models is of paramount importance. Here we introduce a set of invariants for the SU(2)-symmetric Kanamori Hamiltonian which allows to massively speed up the calculation of the fermionic trace in hybridization-expansion continuous-time quantum Monte Carlo algorithms. As an application, we show that, exploiting this set of good quantum numbers, the study of the orbital-selective Mott-transition in systems with up to seven correlated orbitals becomes feasible.

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Nicolaus Parragh, Alessandro Toschi, Karsten Held, Giorgio Sangiovanni. 2012-09-05. Conserved quantities of SU(2)-invariant interactions for correlated fermions and the advantages for quantum Monte Carlo simulations. https://doi.org/10.1103/physrevb.86.155158

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