Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 43: Poster: Correlated Electrons II
TT 43.16: Poster
Mittwoch, 29. März 2023, 15:00–18:00, P2/OG3
Calculating moments for many-electrons systems — •Elaheh Adibi and Erik Koch — Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany
We present a technique for computing the moments ⟨ EM⟩=Tr HM of the many-electron spectrum. Taking the trace over a basis of Slater determinants |I⟩ and expressing the Hamiltonian in the same orbital basis, matrix elements ⟨ I|HM|I⟩ can only be non-zero when the orbital indices of the creation operators are a permutation of those of the annihilation operators. Writing the permutations in cycle notation and realizing that the trace over a cycle with different orbital indices only depends on the number of descends, we can write the trace as a sum over products of Eulerian numbers times binomial factors involving the number of orbitals and electrons.